drm: Remove superflous linux/fb.h includes

Everyone who uses the fbdev emulation helpers doesn't need to include
fb.h directly. Remove it.

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1470847958-28465-3-git-send-email-daniel.vetter@ffwll.ch

drivers/gpu/drm/qxl/qxl_fb.c

@@ -24,7 +24,6 @@
  *     David Airlie
  */
 #include <linux/module.h>
-#include <linux/fb.h>
 
 #include "drmP.h"
 #include "drm/drm.h"