drm: drm_fourcc.h fix includes

Instead of using linux/types.h, drm headers should use drm.h, in order
to handle the portability issues in only one place.

Signed-off-by: Gabriel Laskar <[e-mail]>
Reviewed-by: Emil Velikov <[e-mail]>
CC: Emil Velikov <[e-mail]>
CC: Mikko Rapeli <[e-mail]>

include/uapi/drm/drm_fourcc.h

···
 #ifndef DRM_FOURCC_H
 #define DRM_FOURCC_H
 
-#include <linux/types.h>
+#include "drm.h"
 
 #define fourcc_code(a, b, c, d) ((__u32)(a) | ((__u32)(b) << 8) | \
 				 ((__u32)(c) << 16) | ((__u32)(d) << 24))