tests: arch: arm: arm_runtime_nmi: Add filter for Cortex-M
tests: arch: arm: arm_runtime_nmi: Add filter for Cortex-M

This commit adds a filter to restrict the `arch/arm/arm_runtime_nmi`
test to the ARM Cortex-M platforms only, since this test currently
does not support the Cortex-A and Cortex-R platforms.

Signed-off-by: Stephanos Ioannidis <dc76e9f0c0006e8f919e0c515c66dbba3982f785@stephanos.io>

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