CMake: Move CMAKE_CROSSCOMPILING check inside library CMake

CMake: Update hal and platform stub CMake linker options for coverage ...

- Armclang is not working when we add gcov as target_link_libraries,
modified to pass as linker options with --coverage so it can work armclang and gcc

Fix missing newline

CMake: fix lifflefs filesystem header include path ...

- LittleFileSystem.h and LittleFileSystem.cpp refers to the littflefs headers with the complete path like storage/filesystem/littlefs/littlefs/lfs_util.h and fixed the path issue

CMake: Run the unit tests in travis CI

CMake: Update build tools python modules to pick refactored way of unittest CMake ...

- Update mbed_unittest python module to pick unittest from mbed os root
CMake configuration file
- Add BUILD_TESTING flag ON in test python module

CMake: Update mbed os, unittest CMake and add CMAKE_CROSSCOMPILING guard ...

- Add a new MbedOS project in mbed os root CMake which can be used along with
  BUILD_TESTING conditional check for enabling the unittest build
- Update UNITTEST CMake for setting the CMake configuration like c, cxx flags etc.,
- Add if CMAKE_CROSSCOMPILING conditional check wherever target configuration check
  and toolchain configuration to avoid such configuration gets included for unittest build.

CMake: Fix DTLS socket unittest ...

- Binding the socket address into network stack to avoid socket connect API call hangs in the unittest

CMake: Update target_h stub headers ...

- Avoid using cmsis headers as it brings more redundant dependency into unittest build and for unittest build, all the required OS flags can provide from mbed rtos types header so replaced cmsis header with mbed os types header

CMake: Refactor lorawan unittest cmake ...

- Add CMakeLists.txt file to all lorawan test suite

CMake: Refactore cellular framework unittest ...

- Add CMake configuration file into framework AT, device, common
unittest

CMake: Refactor netsocket unittest CMake ...

- Add Cmake configuration file
- Fix the header inclusion in DTLSSocketWrapper and TLSSocketWrapper test

CMake: Refactor event unittest cmake ...

- Added CMake configuration file into events unittests

CMake: Refactor platform unittest CMake ...

- Add CMake configuration file test suites

CMake: Fix ChainingBlockDevice unittest ...

- ChainingBlockModuleTest test case compares two strings with EXPECT_EQ
which normally compare strings residing memory address so replaced it with EXPECT_STREQ  to compare strings.

CMake: Refactor storage blockdevice and SFDP unittests cmake ...

- Add CMake configuration file
- Fix the header inclusion in blockdevice unittests

CMake: Refactor storage TDBstore and FileSystemStore unittest cmake ...

- Add CMake configuration file in TDBstore and FileSystemStore unittest.

CMake: Refactor drivers unittest cmake

CMake: Remove duplicate documents ...

- Remove the readme as it is a duplicate content of official document
  https://os.mbed.com/docs/mbed-os/v6.9/debug-test/unit-testing.html

CMake: Add add_subdirectory of unittests ...

- add every libraries unittest directory into respective CMake
  which allows to include unittest source into build based on
  MBED_BUILD_UNITTESTS flag

sort stubs into libraries

Merge pull request #14538 from harmut01/cmake-test-mode ...

Cmake: Add MBED_TEST_MODE macro

Merge pull request #14612 from uwrobotics/stm-slave-can-filter-fix ...

CAN: fix slave CAN start filter bank setup

Merge pull request #14626 from jeromecoutant/DEV_STM32WB_1_11_1 ...

STM32WB update drivers version to CUBE V1.11.1

Merge pull request #14624 from 0xc0170/fix-14432 ...

error: use __INITIAL_SP from cmsis instead of RTX one

Merge pull request #14548 from JeanMarcR/STM32F4_NEW_CUBE ...

STM32F4 update drivers version to CUBE V1.26.1

fixup! error: use __INITIAL_SP from cmsis instead of RTX one

Merge pull request #14653 from rwalton-arm/relax_click_version_req ...

requirements: Relax Click version requirement

STM32F4 update drivers version to CUBE V1.26.1

README update STM32F4 to CUBE V1.26.1