msm: camera: reqmgr: Only do self-correction at SOF

Since the SOF timestamp is only updated at SOF,
so we can't do self-correction at EOF. When the
frames already in sync, but the req is a EOF
triggered req, then the req can't be applied at
SOF, but it will fail to pass self-correction
checking at EOF. Then we will loop this progress,
the req can't be applied anymore.

CRs-Fixed: 2930497
Change-Id: I079cbd3cb9ac9541f049c5369baeee831f7444a2
Signed-off-by: Depeng Shao <depengs@codeaurora.org>