drm/rcar-du: Use drm_gem_fb_create()

drm_fb_cma_create() is just a wrapper around drm_gem_fb_create() now,
so use the function directly.

Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NNoralf Trønnes <noralf@tronnes.org>
Reviewed-by: NEric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/1506255985-61113-7-git-send-email-noralf@tronnes.org

drivers/gpu/drm/rcar-du/rcar_du_kms.c

@@ -18,6 +18,7 @@
 #include <drm/drm_crtc_helper.h>
 #include <drm/drm_fb_cma_helper.h>
 #include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_gem_framebuffer_helper.h>
 
 #include <linux/of_graph.h>
 #include <linux/wait.h>
@@ -213,7 +214,7 @@ rcar_du_fb_create(struct drm_device *dev, struct drm_file *file_priv,
 		}
 	}
 
-	return drm_fb_cma_create(dev, file_priv, mode_cmd);
+	return drm_gem_fb_create(dev, file_priv, mode_cmd);
 }
 
 static void rcar_du_output_poll_changed(struct drm_device *dev)