drm/i915: Simplify platform checks in intel_fb_pitch_limit()

Replace the VLV/CHV check with a HAS_GMCH_DISPLAY check in
intel_fb_pitch_limit(), because it's shorter.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170208175328.11064-1-ville.syrjala@linux.intel.com


Reviewed-by: Ander Conselvan de Oliveira <conselvan2@gmail.com>