Remove all source files exclusive to Arm Compiler and IAR (#159) ...

* Remove all source files exclusive to Arm Compiler and IAR

* Also remove 'TOOLCHAIN_ARM'

* Remove targets.json entries for ARM and IAR

GPIO: Use uintptr_t for gpio_irq_api context ...

The HAL gpio_irq_api stores object IDs, which serve as a form of context
for the dispatch of the interrupt handler in the drivers level
InterruptIn Class. The way this is achieved is that the InterruptIn
Class casts its address to uint32_t, which is stored as the ID.
This results in compilation failure when the size of an object pointer
is greater than uint32_t, for example when building on a PC for unit
testing.

In order to allow Unit Testing of the InterruptIn Class, we replace the
use of uint32_t with uintptr_t (type capable of holding a pointer),
which allows portability and expresses intentions more clearly.
In aid of this latter goal, we also replace the use of the name "id"
with "context", to improve clarity - these are addresses of the context
related to that callback.

Update UART pin names & add MBED_CONF_TARGET_STDIO_UART overrides

Add standard pin-names validation script & tests

Merge pull request #14348 from harmut01/baremetal_arm_fm ...

Add bare metal support to ARM FM targets

Add bare metal support to ARM FM targets ...

Modify scatter files to specify heap load region and add small libraries
to list of supported libraries in target.json.

CMake: Create CMSIS library targets to remove dependency on MBED_TARGET_LABELS ...

This goes towards eventually removing reliance on targets.json to specify
the requirements of Mbed targets.

ARM FM CMake: fix CMakeLists names

CMake fvp mps2: fix linking to arm-fm

CMake Arm FM: fix linking libraries with arm-fm ...

Co-authored-by: Hugues Kamba-Mpiana <41612201+hugueskamba@users.noreply.github.com>

CMake ARM FM: fix targets naming

ARM FM: refactor CMake targets

CMake: Add support for all ARM's FM Mbed targets ...

Add CMakeLists.txt files so all ARM's FM Mbed targets can be built with CMake

Add SPDX license identifier to Arm files ...

Add license identifier to files which Arm owns the copyright to,
and contain either BSD-3 or Apache-2.0 licenses. This is to address
license errors raised by scancode analysis.

stack: armc: Workaround config passing bug ...

Workaround a bug where the boot stack size configuration option is not
passed on to armlink, the Arm Compiler's linker. Prefer
MBED_CONF_TARGET_BOOT_STACK_SIZE if present, as this is what the
configuration system should provide. Fall back to MBED_BOOT_STACK_SIZE
if MBED_CONF_TARGET_BOOT_STACK_SIZE is not defined, as in the case of
buggy tools. If both MBED_CONF_TARGET_BOOT_STACK_SIZE and
MBED_BOOT_STACK_SIZE are not defined, then we fall back to a hard-coded
value provided by the linkerscript. See
https://github.com/ARMmbed/mbed-os/issues/13474 for more information.

Use boot stack size from config system ...

To allow overriding of the boot stack size from the Mbed configuration
system, consistently use MBED_CONF_TARGET_BOOT_STACK_SIZE rather than
MBED_BOOT_STACK_SIZE.

Fixes #10319

Clean up ARM toolchain heap+stack setup in targets ...

ARM Compiler 6.13 testing revealed linker errors pointing out
conflicting use of `__user_setup_stackheap` and
`__user_initial_stackheap` in some targets. Remove the unwanted
`__user_initial_stackheap` from the targets - the setup is
centralised in the common platform code.

Looking into this, a number of other issues were highlighted

* Almost all targets had `__initial_sp` hardcoded in assembler,
  rather than getting it from the scatter file. This was behind
  issue #11313. Fix this generally.
* A few targets' `__initial_sp` values did not match the scatter
  file layout, in some cases meaning they were overlapping heap
  space. They now all use the area reserved in the scatter file.
  If any problems are seen, then there is an error in the
  scatter file.
* A number of targets were reserving unneeded space for heap and
  stack in their startup assembler, on top of the space reserved in
  the scatter file, so wasting a few K. A couple were using that
  space for the stack, rather than the space in the scatter file.

To clarify expected behaviour:

* Each scatter file contains empty regions `ARM_LIB_HEAP` and
  `ARM_LIB_STACK` to reserve space. `ARM_LIB_STACK` is sized
  by the macro `MBED_BOOT_STACK_SIZE`, which is set by the tools.
  `ARM_LIB_HEAP` is generally the space left over after static
  RAM and stack.
* The address of the end of `ARM_LIB_STACK` is written into the
  vector table and on reset the CPU sets MSP to that address.
* The common platform code in Mbed OS provides `__user_setup_stackheap`
  for the ARM library. The ARM library calls this during startup, and
  it calls `__mbed_user_setup_stackheap`.
* The default weak definition of `__mbed_user_setup_stackheap` does not
  modify SP, so we remain on the boot stack, and the heap is set to
  the region described by `ARM_LIB_HEAP`. If `ARM_LIB_HEAP` doesn't
  exist, then the heap is the space from the end of the used data in
  `RW_IRAM1` to the start of `ARM_LIB_STACK`.
* Targets can override `__mbed_user_setup_stackheap` if they want.
  Currently only Renesas (ARMv7-A class) devices do.
* If microlib is in use, then it doesn't call `__user_setup_stackheap`.
  Instead it just finds and uses `ARM_LIB_STACK` and `ARM_LIB_HEAP`
  itself.

FASTMODEL: add a comment for TRNG simulation

FASTMODEL: update trng based on comments

FASTMODEL: add simulated TRNG implementation to fastmodel

FVP_MPS2: Fix serial_init when FC is not used ...

After adding DEVICE_SERIAL_FC guards to serial_api.h
serial_set_flow_control is not available. In case of this
implementation, this function is a no-op and may be safely removed.

Merge pull request #10619 from jamesbeyond/fm-iap ...

Fastmodel: enable flashIAP and kvstore

HAL I2C: adds missing DEVICE_I2C guards

correct CMSDK for M0Plus due to MPU is not presented

FastModel: change Fastmodel memory layout regions from 3 to 2 ...

- change memoryzones.h
 - change linker scripts for each toolchains

ARM SSG/FM: Cope correctly with NC GPIO

FastModel: Add SPDX License Identifier

FastModel: refactor us_ticker code, make names intuitive ...

- reanme US_TICKER_TIMER1 to US_TICKER_COUNTER
 - reanme US_TICKER_TIMER2 to US_TICKER_INTERRUPT

FastModel: add HAL sleep implementation

Fastmodel: add HAL low-power ticker implementation