disp: msm: sde: fix frame event signal for cwb

Submit a cwb frame event signal to notify the crtc that cwb
is completed. Currently cwb also uses the same frame done
event as primary. When a single cwb commit is completed, because
cwb is on a slower path there is a race condition in which the
subsequent frame done event for primary clears the refcount.
This fix isolates the events and removes this situation.

Change-Id: Ic3e18302eb8a497cbd7a00f271de2ab320576c83
Signed-off-by: Nilaan Gunabalachandran <ngunabal@codeaurora.org>

msm/sde/sde_encoder.h

@@ -45,6 +45,7 @@
 #define SDE_ENCODER_FRAME_EVENT_PANEL_DEAD		BIT(2)
 #define SDE_ENCODER_FRAME_EVENT_SIGNAL_RELEASE_FENCE	BIT(3)
 #define SDE_ENCODER_FRAME_EVENT_SIGNAL_RETIRE_FENCE	BIT(4)
+#define SDE_ENCODER_FRAME_EVENT_CWB_DONE		BIT(5)
 
 #define IDLE_POWERCOLLAPSE_DURATION	(66 - 16/2)
 #define IDLE_POWERCOLLAPSE_IN_EARLY_WAKEUP (200 - 16/2)