gpu: add module.h to drivers/gpu files as required.

So that we don't get build failures once the implicit module.h
presence is removed.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

drivers/gpu/drm/drm_fb_helper.c

@@ -31,6 +31,7 @@
 #include <linux/sysrq.h>
 #include <linux/slab.h>
 #include <linux/fb.h>
+#include <linux/module.h>
 #include "drmP.h"
 #include "drm_crtc.h"
 #include "drm_fb_helper.h"