drm/i915: Handle YUV subpixel support better

drm/i915: Handle YUV subpixel support better

Y41x formats is a 4:4:4 format, so it can be addressed with pixel level accuracy.
Meanwhile it seems that while rotating YUYV 4:2:2 formats need a multiple of 2
for width and height, otherwise corruption occurs.

For YUV 4:2:2, the spec says that w/h should always be even, but we get
away with odd height while unrotated. When rotating it seems corruption
occurs with an odd x/y, and w/h should always be even.
Just to be completely paranoid, reject odd x/y w/h when rotating 90/270.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190322135954.20434-1-maarten.lankhorst@linux.intel.com
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>