arch/arc: Add hook for CONFIG_SCHED_THREAD_USAGE accounting in ISRs
arch/arc: Add hook for CONFIG_SCHED_THREAD_USAGE accounting in ISRs

Call into z_thread_usage_stop() before ISR entry to avoid including
interrupt handling totals in thread usage stats.

Signed-off-by: Andy Ross <c70f9a6bf6ee0cd69c8af4ce5e6b131945769315@intel.com>

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