tests: cmsis_rtos_v2: Enhance event flags tests
tests: cmsis_rtos_v2: Enhance event flags tests

Add negative tests for event flags supported in
CMSIS RTOS V2 layer.

Signed-off-by: Spoorthi K <c4ff46ff4cba9c2c6c6c9d55497ae534451b4309@intel.com>

GiulianoFranchetto/zephyr,explora26/zephyr,galak/zephyr,explora26/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,ldts/zephyr,nashif/zephyr,ldts/zephyr,punitvara/zephyr,nashif/zephyr,nashif/zephyr,ldts/zephyr,ldts/zephyr,explora26/zephyr,finikorg/zephyr,nashif/zephyr,GiulianoFranchetto/zephyr,punitvara/zephyr,punitvara/zephyr,GiulianoFranchetto/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,ldts/zephyr,galak/zephyr,punitvara/zephyr,GiulianoFranchetto/zephyr,Vudentz/zephyr,explora26/zephyr,galak/zephyr,GiulianoFranchetto/zephyr,galak/zephyr,finikorg/zephyr,Vudentz/zephyr,Vudentz/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,Vudentz/zephyr,finikorg/zephyr,Vudentz/zephyr,finikorg/zephyr,Vudentz/zephyr,explora26/zephyr,punitvara/zephyr,zephyrproject-rtos/zephyr,nashif/zephyr