msm: camera: reqmgr: Add initial sync support

Do the initial sync by SOF timestamp, if the gap
between the initial SOF of link and the last SOF
of sync link is less than half of frame druation,
CRM should abandon this frame since this frame
should sync with next frame of sync link.

Change-Id: I204e3ed49bcf4ac7424aaf5109ad5ce3bc3a2789
Signed-off-by: Depeng Shao <depengs@codeaurora.org>