include/mutex: Use inotifywait to improve performance

include/mutex: Use inotifywait to improve performance

The current mutex implementation uses sleep to periodically check if
the lock can be acquired. This causes a lot of latency for short waits
and a lot of unnecessary sleep/wakeup cycles for long waits.
This commit changes the mutex implementation to use inotifywait
instead of sleep, increasing mutex performance for both short and long
waits.