drm/i915: Pass intel_plane and intel_crtc to plane hooks

Streamline things by passing intel_plane and intel_crtc instead of
the drm types to our plane hooks.

v2: s/ilk/g4x/ in sprite code

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170327185546.2977-3-ville.syrjala@linux.intel.com