kernel: mutex: fix races when lock timeout

Say threadA holds a mutex and threadB tries
to lock it with a timeout, a race would occur
if threadA unlock that mutex after threadB
got unpended by sys_clock and before it gets
scheduled and calls k_spin_lock.

This patch fixes this issue by checking the
mutex's status again after k_spin_lock calls.

Fixes #48056

Signed-off-by: Qi Yang <qi.yang@cmind-semi.com>