drm: bridge: dw-hdmi: add HDMI vendor specific infoframe config

Vendor specific infoframe is mandatory for 4K2K resolution.
Without this, the HDMI protocol compliance fails.

Signed-off-by: Nickey Yang <nickey.yang@rock-chips.com>
Reviewed-by: Jose Abreu <joabreu@synopsys.com>
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Link: http://patchwork.freedesktop.org/patch/msgid/1490081777-2232-1-git-send-email-nickey.yang@rock-chips.com