cpu/esp_common/freertos: lock/unlock mutex if scheduling is not active
cpu/esp_common/freertos: lock/unlock mutex if scheduling is not active

If module `core_mutex_priority_inheritance` is enabled, the scheduling has to be active to lock/unlock the mutex/rmutex used by FreeRTOS semaphores. If scheduling is not active FreeRTOS semaphore function always succeed.
RIOT-OS/RIOT,RIOT-OS/RIOT,ant9000/RIOT,ant9000/RIOT,ant9000/RIOT,kYc0o/RIOT,kYc0o/RIOT,miri64/RIOT,miri64/RIOT,miri64/RIOT,kaspar030/RIOT,ant9000/RIOT,kaspar030/RIOT,jasonatran/RIOT,jasonatran/RIOT,kaspar030/RIOT,kYc0o/RIOT,kYc0o/RIOT,kaspar030/RIOT,miri64/RIOT,jasonatran/RIOT,RIOT-OS/RIOT,kaspar030/RIOT,RIOT-OS/RIOT,miri64/RIOT,kYc0o/RIOT,ant9000/RIOT,RIOT-OS/RIOT,jasonatran/RIOT,jasonatran/RIOT