tests: improve test case descriptions of some interrupt APIs
tests: improve test case descriptions of some interrupt APIs

To add some test case descriptions for testing irq_lock(), irq_unlock()
, irq_enable(), irq_disable().

Signed-off-by: Enjia Mai <233e651694b7770d0f980a273a8e4a6f7e2a84d4@intel.com>

Vudentz/zephyr,nashif/zephyr,finikorg/zephyr,nashif/zephyr,Vudentz/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,Vudentz/zephyr,galak/zephyr,galak/zephyr,nashif/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,Vudentz/zephyr,zephyrproject-rtos/zephyr,Vudentz/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,nashif/zephyr,Vudentz/zephyr,galak/zephyr,galak/zephyr,nashif/zephyr,galak/zephyr