msm: mdss: Add HDR Metadata Interface

Define an interface to help user-space to pass the HDR stream
information to the driver which will be used in configuring HDMI
and DP interfaces.
Use the new interface in HDMI and make necessary changes while
reading the info.

CRs-Fixed: 2004813
Change-Id: I3447c7b2ad5c4ca072becbeb2201e27c4f57c1dd
Signed-off-by: Arun Kumar K.R <akumarkr@codeaurora.org>