dmr/msm/sde: propagate correct fence_event to sde_fence_signal

Propagate the fence_event correctly from the
frame_event_work to fence_signal. Currently
the state is moved to a boolean in the intermediate
functions leading to wrong fence_event propagated.

Change-Id: If7df50e5ef2d79c49f8d72cdb32eb45c5fb87ee6
Signed-off-by: Veera Sundaram Sankaran <veeras@codeaurora.org>