This adds a test that attempts to submit a work with 0 timeout thus
causing it to immediatelly be submitted to the queue so it is pending
execution which is then cancelled with k_delayed_work_cancel.
Note this can only be done with coop threads with the same or higher
priority otherwise the work_q thread is wakeup before
k_delayed_work_cancel takes place, thus why test_delayed_cancel uses
K_HIGHEST_THREAD_PRIO.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
