drm/fb-helper: Fix sparse warnings

drm/drm_fb_helper.c:2306:12: warning: symbol 'drm_fb_helper_modinit' was not declared. Should it be static?

While at it, move the lefover static inline to the right place.

Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1474292035-15695-4-git-send-email-ville.syrjala@linux.intel.com
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index c4d3500..5e83028 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -41,6 +41,8 @@
 #include <drm/drm_atomic.h>
 #include <drm/drm_atomic_helper.h>
 
+#include "drm_crtc_helper_internal.h"
+
 static bool drm_fbdev_emulation = true;
 module_param_named(fbdev_emulation, drm_fbdev_emulation, bool, 0600);
 MODULE_PARM_DESC(fbdev_emulation,