mdss: display-port: add support for suspend and resume events

Add support for suspend and resume events that are
triggered by the run time system. In particular, transition
the clock (link and core) and regulators state depending
on whether the suspend or resume is being processed.

CRs-Fixed: 1103664
Change-Id: I4e3de9b32963c71dfded0f695dc7734b8121e19a
Signed-off-by: Chandan Uddaraju <chandanu@codeaurora.org>