In POMS use case, the handling of the wait for vsync event
completion coincides with the concurrent
drm_crtc_funcs.enable_vblank. This concurrency causes a vsync
event complete timeout while disabling the encoder. to fix this
concurrency problem, increment the vblank refcount in encoder
disable and release the vblank refcount in encoder enable.
Change-Id: I79671e4a2bafdd01a6b2523a80fe511bff23d6b6
Signed-off-by: Akash Gajjar <quic_agajjar@quicinc.com>