drm: rcar-du: Refactor Feature and Quirk definitions

These flags are represented by bit fields. To make this clear, utilise
the BIT() macro.
Signed-off-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

drivers/gpu/drm/rcar-du/rcar_du_drv.h

@@ -23,11 +23,11 @@ struct drm_device;
 struct drm_fbdev_cma;
 struct rcar_du_device;
 
-#define RCAR_DU_FEATURE_CRTC_IRQ_CLOCK	(1 << 0)	/* Per-CRTC IRQ and clock */
-#define RCAR_DU_FEATURE_EXT_CTRL_REGS	(1 << 1)	/* Has extended control registers */
-#define RCAR_DU_FEATURE_VSP1_SOURCE	(1 << 2)	/* Has inputs from VSP1 */
+#define RCAR_DU_FEATURE_CRTC_IRQ_CLOCK	BIT(0)	/* Per-CRTC IRQ and clock */
+#define RCAR_DU_FEATURE_EXT_CTRL_REGS	BIT(1)	/* Has extended control registers */
+#define RCAR_DU_FEATURE_VSP1_SOURCE	BIT(2)	/* Has inputs from VSP1 */
 
-#define RCAR_DU_QUIRK_ALIGN_128B	(1 << 0)	/* Align pitches to 128 bytes */
+#define RCAR_DU_QUIRK_ALIGN_128B	BIT(0)	/* Align pitches to 128 bytes */
 
 /*
  * struct rcar_du_output_routing - Output routing specification