msm: vidc: Don't free OCMEM when there is an open video instance

Currently, vidc enters power collapse after a video has been paused
for 10 seconds; however, the video instance is not closed. Resuming
the video after vidc has entered power collapse causes our vidc
firmware to crash, thus breaking video functionality until the device
is rebooted.

Not freeing OCMEM during power collapse in the middle of an open
video instance works around this issue and is good enough until
the underlying issue has been fixed.

Change-Id: Ieb69e552b860941c43d959dc7bea0c938abbd5bc
Signed-off-by: Sultanxda <sultanxda@gmail.com>

Conflicts:
	drivers/media/platform/msm/vidc/venus_hfi.c