msm: camera: isp: Cleanup the start/stop/release functions

The error path flow for start_hw has been updated to cleanup specific
parts instead of complete stop_hw call. The redundant state check in
release is also removed and return positive even if state is bad. The
Safe enable/disable is moved outside the start_only/stop_only check
to reduce the runtime switch and avoid any runtime TZ errors.

Change-Id: I1ccedc4285eaad7885f3a5fcffe6303a919a6dd4
Signed-off-by: Harsh Shah <harshs@codeaurora.org>
Signed-off-by: Venkat Chinta <vchinta@codeaurora.org>