HACK: gfx: Adjust HDMI hdisplay/vdisplay values

HACK: gfx: Adjust HDMI hdisplay/vdisplay values

The HDMI code doesn't follow the KMS desing correctly, hence the values
stored in the mode structure are incorrect. Adjust the "user" mode
hdisplay/vdisplay and their crtc counterparts to match the framebuffer
size. This "fixes" vblank counter comparisons for HDMI, thus fixing page
flip completion detection, and this also allows the overlay to be
clipped "correctly".

This makes assumptions on how the panel fitter willl be programmed.
Based on a cursory examination of the HDMI code, it will only work
as long as the IPIL_TIMING_SCALE_ASPECT scaling mode is selected.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>