msm: camera2: cpp: Remove the reinstallation of cpp_timer

when msm_cpp_do_timeout_work is running, it's possible that the
cpp_timer is pending again. So if we setup this timer in the work
again, it will initialize the timer list entry without any
synchronization. If other context is accessing the global timer
list, it will found one of the node being corrupted. And finally
system crashes. Actually we don't need to reinstall the timer
because the callback function and private data don't change at all.

Change-Id: I84487a6c599427e4b6a96ef4e947e8c1d85115b6
CRs-Fixed: 637802
Signed-off-by: Figo Wang <figow@codeaurora.org>