drm/i915: Also give the sprite width for WM computation

In the future, we'll need the height of the fb to fetch from memory for
WM computation.

Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --cc drivers/gpu/drm/i915/i915_drv.h
Simple merge

diff --cc drivers/gpu/drm/i915/intel_drv.h
Simple merge

diff --cc drivers/gpu/drm/i915/intel_pm.c
Simple merge

diff --cc drivers/gpu/drm/i915/intel_sprite.c
Simple merge