DRM: Add support for HDMI content type
Some monitors expose a selector for the kind of content that will get displayed, allowing them to optimise their settings for this particular content type.
I got access to such a monitor, sadly even setting it to game mode didn’t lower its atrocious latency, but drm_info reports it to be set correctly so hopefully it’ll work better with other monitors.
Signed-off-by: Emmanuel Gil Peyrot linkmauve@linkmauve.fr