drm/sun4i: backend: Fix structure indentation

The sun4i_plane_desc structure was somehow indented to two tabulations
instead of one as we shoud do. Fix that.
Acked-by: NChen-Yu Tsai <wens@csie.org>
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Link: https://patchwork.freedesktop.org/patch/msgid/8a6714bddb865adfcfe2b792e406a2f10bb819bc.1516617243.git-series.maxime.ripard@free-electrons.com

drivers/gpu/drm/sun4i/sun4i_layer.c

@@ -20,10 +20,10 @@
 #include "sunxi_engine.h"
 
 struct sun4i_plane_desc {
-	       enum drm_plane_type     type;
-	       u8                      pipe;
-	       const uint32_t          *formats;
-	       uint32_t                nformats;
+	enum drm_plane_type     type;
+	u8                      pipe;
+	const uint32_t          *formats;
+	uint32_t                nformats;
 };
 
 static void sun4i_backend_layer_reset(struct drm_plane *plane)