cavs: (cosmetic) clean up and simplification of intc_cavs.c
cavs: (cosmetic) clean up and simplification of intc_cavs.c

1. don't use "inline" in .c, let the compiler decide
2. remove superfluous parentheses
3. simplify a function by directly returning the result of a boolean
operation

Signed-off-by: Guennadi Liakhovetski <974fc78730de35b120231422a86eeefcb293601e@linux.intel.com>

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