msm: camera: reqmgr: Add provision to obtain exposure time

Currently CRM watchdog timer expiry is fixed at 1 second.
This will not hold good if the sensor exposure time is increased
beyond 1 second. In such situations obtain the time from userspace,
and modify the CRM watchdog timer accordingly.

CRs-Fixed: 2530691
Change-Id: I6251bcb2b915a9e317caffd350220e249214c8b2
Signed-off-by: Karthik Anantha Ram <kartanan@codeaurora.org>
Signed-off-by: Mukund Madhusudan Atre <matre@codeaurora.org>