msm: vidc: Cancel the queued work after deleting the timer

Cancel the queue work while cleaning up the instance after
deleting the timer. Timer deletion will ensure no work will
be scheduled further and cancel_work_sync will ensure to
cancel the work that has not completed its execution yet
during cleaning up the instance.

Change-Id: Ifd5c2264e9ff1930c6d1b05859e75bc8238a35b6
Signed-off-by: Priyanka Gujjula <pgujjula@codeaurora.org>