drm/msm: add event support in sde rsc

Add core_powercollapse, core_restore, solver_enabled,
solver_disabled, etc. events support in sde rsc
driver. Client can request for multiple events
with single call.

Change-Id: Ic0ece204d7b44eb3357fadd7b4071f554658042c
Signed-off-by: Dhaval Patel <pdhaval@codeaurora.org>