msm: camera: ope: Synchronize flush and submit BLs

In stability, Flush and submit can run in parallel.
This can cause submit to fail for a given request.
Avoid submitted new request if it is lesss than last
flush request.

CRs-Fixed: 2622981
Change-Id: Idf94e39d8cd74f25cc05c8211301e9c172b8a88a
Signed-off-by: Alok Chauhan <alokc@codeaurora.org>