drm: renesas: shmobile: Use %p4cc to print fourcc code

Replace the last printing of an hexadecimal fourcc format code by a
pretty-printed format name, using the "%p4cc" format specifier.
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/aaa9d474535f3cd800da5a9ef27023dc7960e690.1694767209.git.geert+renesas@glider.be

drivers/gpu/drm/renesas/shmobile/shmob_drm_plane.c

@@ -184,8 +184,8 @@ shmob_drm_plane_update(struct drm_plane *plane, struct drm_crtc *crtc,
 
 	format = shmob_drm_format_info(fb->format->format);
 	if (format == NULL) {
-		dev_dbg(sdev->dev, "update_plane: unsupported format %08x\n",
-			fb->format->format);
+		dev_dbg(sdev->dev, "update_plane: unsupported format %p4cc\n",
+			&fb->format->format);
 		return -EINVAL;
 	}