drm/sun4i: drop use of drmP.h

Drop use of the deprecated drmP.h header file.

While touching the list of include file, use the typical order of the
blocks:
\#include <linux/*>

\#include <video/*>

\#include <drm/*>

\#include ""

Within each block, sort the files.
Include necessary files to fix build after the drmP.h removal.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Emil Velikov <emil.velikov@collabora.com>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: https://patchwork.freedesktop.org/patch/msgid/20190716064220.18157-6-sam@ravnborg.org

drivers/gpu/drm/sun4i/sun4i_frontend.c

@@ -3,9 +3,6 @@
  * Copyright (C) 2017 Free Electrons
  * Maxime Ripard <maxime.ripard@free-electrons.com>
  */
-#include <drm/drmP.h>
-#include <drm/drm_gem_cma_helper.h>
-#include <drm/drm_fb_cma_helper.h>
 
 #include <linux/clk.h>
 #include <linux/component.h>
@@ -16,6 +13,13 @@
 #include <linux/regmap.h>
 #include <linux/reset.h>
 
+#include <drm/drm_device.h>
+#include <drm/drm_fb_cma_helper.h>
+#include <drm/drm_fourcc.h>
+#include <drm/drm_framebuffer.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_plane.h>
+
 #include "sun4i_drv.h"
 #include "sun4i_frontend.h"