drm/rect: Add DRM_RECT_INIT() macro

Add a helper macro to initialize a rectangle from x, y, width and
height information.

Reviewed-by: Jani Nikula <[e-mail]>
Reviewed-by: David Gow <[e-mail]>
Acked-by: Thomas Zimmermann <[e-mail]>
Signed-off-by: José Expósito <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

include/drm/drm_rect.h

···
 };
 
 /**
+ * DRM_RECT_INIT - initialize a rectangle from x/y/w/h
+ * @x: x coordinate
+ * @y: y coordinate
+ * @w: width
+ * @h: height
+ *
+ * RETURNS:
+ * A new rectangle of the specified size.
+ */
+#define DRM_RECT_INIT(x, y, w, h) ((struct drm_rect){ \
+		.x1 = (x), \
+		.y1 = (y), \
+		.x2 = (x) + (w), \
+		.y2 = (y) + (h) })
+
+/**
  * DRM_RECT_FMT - printf string for &struct drm_rect
  */
 #define DRM_RECT_FMT    "%dx%d%+d%+d"