drm/rect: Add drm_rect_translate_to()

Add a helper to translate a rectangle to an absolute position.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190930134214.24702-1-ville.syrjala@linux.intel.comReviewed-by: Jani Nikula <jani.nikula@intel.com>

include/drm/drm_rect.h

@@ -106,6 +106,20 @@ static inline void drm_rect_translate(struct drm_rect *r, int dx, int dy)
 	r->y2 += dy;
 }
 
+/**
+ * drm_rect_translate_to - translate the rectangle to an absolute position
+ * @r: rectangle to be tranlated
+ * @x: horizontal position
+ * @y: vertical position
+ *
+ * Move rectangle @r to @x in the horizontal direction,
+ * and to @y in the vertical direction.
+ */
+static inline void drm_rect_translate_to(struct drm_rect *r, int x, int y)
+{
+	drm_rect_translate(r, x - r->x1, y - r->y1);
+}
+
 /**
  * drm_rect_downscale - downscale a rectangle
  * @r: rectangle to be downscaled