video: rockchip: hdmi: support hdr function

video: rockchip: hdmi: support hdr function

HDR is introduced by HDMI2.0a, which need parsing HDR Static
Metedata data Block defined in EDID, and send Dynamic Range
and Mastering InfoFrame to inform TV to switch to HDR mode.

If TV support HDR, it's EOTF is shown in sysfs node
/sys/class/display/HDMI/color with key word "Supported EOTF:".

For example, "Support EOTF: 0x7" means support following EOTF:
BIT0: Traditional gamma - SDR
BIT1: Traditional gamma - HDR
BIT2: ST_2084

To switch eotf mode, you can use following command:
echo hdr=value > /sys/class/display/HDMI/color
value could be:
	0 - Disable sending Dynamic Range and Mastering InfoFrame
	1 - Traditional gamma - SDR
	2 - Traditional gamma - HDR
	4 - ST_2084
0、1 both means SDR mode， 4 is HDR10/Dolby HDR mode.

Change-Id: Ia3d19bbca9b9368cde8dcb11265fbff4684ac603
Signed-off-by: Zheng Yang <zhengyang@rock-chips.com>
(cherry picked from commit 08ea9d12f34f8ea6f79bdd5b7eb1ff74d2cd796f)