msm: camera: isp: Return error if scheduling is delayed

Hardware writes into ping / pong address in alternate frames.
Software maintains a counter for sof and increments it when
sof irq is received from hardware. If scheduling is delayed,
software book-keeping logic goes wrong because hardware ping /
pong address switches back and forth while software is unable
to track it due to scheduling delay. Add logic for software
ping / pong logic and validate against hardware irq. If there
is mismatch, report error to avoid page fault issues.

Change-Id: I1797cbb3f34c8e4a0dffecbdf92e66674f02d2f1
Signed-off-by: Senthil Kumar Rajagopal <skrajago@codeaurora.org>