Add reference to CMSIS RTOS2 example.

Author: dmitrykos

interop/cmsis/rtos2/README.md

@@ -2,6 +2,8 @@
 
 STK provides a complete **CMSIS-RTOS2** compatibility layer (`cmsis_os2_stk.cpp`) that maps the standard ARM [CMSIS-RTOS2 C API](https://arm-software.github.io/CMSIS_6/latest/RTOS2/group__CMSIS__RTOS.html) (`cmsis_os2.h` v2.3.0) onto the STK C++ kernel. This allows you to use STK as a drop-in RTOS backend in any project that targets the CMSIS-RTOS2 interface, including code generated by STM32CubeMX, MCUXpresso, or any other CMSIS-aware IDE or middleware stack.
 
+See reference [CMSIS-RTOS2 example](https://github.com/SuperTinyKernel-RTOS/stk/tree/main/build/example/project/eclipse/stm/blinky-cmsis-rtos2-stm32f407g-disc1/src) for STM32F407G-DISC1 development board.
+
 ## Supported API Groups
 
 | API Group         | Functions Covered                                                                                                                                                                                                                                                                                                                                  |