kgsl/drm: Enable IRQ sharing from MDP

This patch adds IRQ sharing mechanism for MDP and KGSL DRM.
DRM clients requires IRQ for the respective CRTC to trigger/
acknowledge the buffer submission to MDP.

IRQ from primary crtc will be used to trigger the buffer
submission.
IRQ from HDMI, WFD and Rotator will be use to acknowledge the
buffer consumption from MDP.

Change-Id: I0fea3b83772c478ece3dfd3042bd1193c4da2726
Signed-off-by: Beeresh Gopal <gbeeresh@codeaurora.org>