If the input is ADV7604_INPUT_VGA_RGB and RGB quantization range is
set to V4L2_DV_RGB_RANGE_AUTO, video with CEA timings will be
received as RGB. For ADV7604_INPUT_VGA_COMP, automatic CSC mode
will be selected.
See table 44 on page 205 in "ADV7604 Hardware Manual, Rev. F, August 2010"
for details.