Merge pull request #6273 from bulislaw/update_cmsis_5.3 ...

Update cmsis/rtx to version 5.3

CMSIS: Move non-config includes behind PTIM ifdef ...

That is to enabled integration with build-it-all Mbed OS type build
system.

Cherry-picked from CMSIS_5 repo: e8d0a476

CMSIS/RTX: Fix using FALSE/TRUE with preprocesor

RTX5: uVisor: Remove static from svcRtxKernelUnlock/Lock to support uVisor

RTX5: uVisor: Defer to uVisor for SVCall priority ...

Only set the SVCall priority if uVisor is not present. If uVisor is
present, keep using whatever priorities it has already set up.

RTX5: uVisor: Add OsEventObserver ...

Add the OsEventObserver mechanism. A client interested in receiving
notifications on certain OS events can register to receive notifications
with osRegisterForOsEvents. This is useful for clients like the secure
memory allocator, which observes thread switching events in order to
swap in and out different memory allocator objects.

RTX5: uVisor: Extend thread control block with context ...

OsEventObserver objects expect a context to be maintained per thread on
their behalf. Add this context to the thread control block and extend
the thread creation functions with the ability to supply a context.

RTX5: uVisor: Use OsEventObserver

RTX5: uVisor: Switch threads very carefully ...

uVisor doesn't set the PSP of the target thread. The RTOS sets the PSP
of the target thread from the target thread's TCB. However, when
interrupts of higher priority than PendSV happen between the call to
uVisor to switch boxes, and the RTOS setting PSP, the uVisor vIRQ
interrupt handler will attempt to use an invalid PSP (the PSP from
before the box and thread switch). This leads to a crash. Make box and
thread switching atomic by disabling interrupts immediately before the
box switching until immediately after the new PSP is set.

CMSIS/RTX: Update idle handler and SysTick ops

CMSIS/RTX: Pre-processor defines used for assembly ...

CMSIS repo does not support pre-processor defines, hence multiple assembly
files are added for secure/non-secure and floating point tools.

Mbed OS tools support assembly file pre-processing, but the build system
does not support multiple assembly files for each target, hence updating
the assembly files.

CMSIS/RTX: Allow overwriting mutex ops for ARMC

CMSIS/RTX: Patch RTX so irq_cm4f.s files work with no FPU targets

CMSIS/RTX: Patch RTX4 to preserve osThreadDef compatibility ...

mbed OS used older RTX4 version and with osThreadDef accepting only 3
parameters, to preserve compatibility we hardcode the 'instances'
parameter to 1.

(cherry picked from commit 428acae)

[CMSIS_5]: Updated to 49ac527a

Cleanup ...

1. Enable watermark to get stack space information
2. Restructured code
3. Throw error if MBED_THREAD_STATS_ENABLED is not set
4. Astyle changes

Merge pull request #6784 from deepikabhavnani/mbed_stats_fix ...

Add common define MBED_ALL_STATS_ENABLED to enable all statistics

Add stats header file to mbed.h ...

All API header files should be part of mbed.h

Merge pull request #6654 from kjbracey-arm/fault_cr ...

Add missing carriage returns to fault handler

Add MBED_CONF_APP_TIMER/IDLE_THREAD_STACK_SIZE to configure timer/idle thread stack size by application

Change back default size of timer thread stack ...

Configuration for changing this size is kept.

Enlarge timer thread stack size for Cortex-M23/M33

Add common define to enable all statistics ...

As part of Device Health requirement, all mbed OS statistics should be
enabled with single macro `MBED_ALL_STATS_ENABLED`

Support RTOS-less secure image build with Cortex-M23/M33

Merge pull request #6534 from c1728p9/rtos_suspend ...

Update idle loop to reduce calls to suspend

Merge pull request #6486 from deepikabhavnani/thread_class_tz ...

Thread class tz

Add missing carriage returns to fault handler ...

Fault handler was outputting just LFs between lines, when standard
terminals require CR+LF, leading to messy output.

RTOS: SysTimer: Update tests ...

Use a mock ticker object instead of the lp_ticker for update_tick() and get_time() tests.

Added description of tz_module and MBED_TZ_DEFAULT_ACCESS

Update idle loop to reduce calls to suspend ...

Change tickless handling to use public RTX calls and to prevent
unnecessary calls to suspend/resume by looping until the kernel
needs to be resumed.