drm/i915: Pass the actual sprite width to watermarks functions

Don't subtract one from the sprite width before watermark calculations.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index f9813b3..9ef476b 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -2641,7 +2641,7 @@
 		if (intel_plane->pipe == pipe) {
 			intel_plane->wm.enabled = enabled;
 			intel_plane->wm.scaled = scaled;
-			intel_plane->wm.horiz_pixels = sprite_width + 1;
+			intel_plane->wm.horiz_pixels = sprite_width;
 			intel_plane->wm.bytes_per_pixel = pixel_size;
 			break;
 		}