gpu: host1x: Port the HDMI vendor infoframe code the common helpers
I just wrote the bits to define and pack HDMI vendor specific infoframe.
Port the host1x driver to use those so I can refactor the infoframe code
a bit more.
This changes the length of the infoframe payload from 6 to 5, which is
enough for the "frame packing" stereo format.
v2: Pimp up the commit message with the note about the length
(Ville Syrjälä)