DRM_FORMAT_NV20 and DRM_FORMAT_NV30 is a 2 plane format suitable for
linear layouts, this two format is similar to NV15 has no padding
between component, but NV15 is 4:2:0 sub-sampling, NV20 is 4:2:2
sub-sampling and NV30 is no-sampling.
The '20' and '30' suffix refers to the optimum effective bits per
pixel which is achieved.
Signed-off-by: Sandy Huang <hjc@rock-chips.com>
Change-Id: I84da7e03125e675f274c6307128b4b7b307767cc
9fad8c5fa8