msm: camera: isp: Reset overflow pending flag in start hw

While start hw, either a fresh start or resume after flush,
reset the overflow pending flag as we reset the hw and start
fresh with applying init packet. In case where overflow happening
at the same time as halt immediately, we set overflow pending
flag to true. Eventhough while halt immediate and resume
scenario, we reset the hw, not resetting overflow pending flag
causes not to apply any new packets while resume.

CRs-Fixed: 2565049
Change-Id: Ia9c871402343306945fe1b8f8373659e52630fe2
Signed-off-by: Pavan Kumar Chilamkurthi <pchilamk@codeaurora.org>