drm/i915: Add local 'fb' variables
Add a local 'fb' variable to a few places to get rid of the
'crtc->primary->fb' stuff. Looks neater and helps me with my poor
coccinelle skills later.
While at it switch over to using the pixel format rather than
depth+bpp.
Cc: intel-gfx@lists.freedesktop.org
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1479498793-31021-2-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>