drm/fb-helper: unexport drm_fb_helper_single_fb_probe

Not called by anyone, and really, shouldn't be. Drivers are supposed
either drm_fb_helper_initial_config or drm_fb_helper_hotplug_event.
Originally this was done differently, but is now consolidated in the
helper functions and no longer done by drivers directly.

Reviewed-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index eaab092..f5d3626 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -754,8 +754,8 @@
 }
 EXPORT_SYMBOL(drm_fb_helper_pan_display);
 
-int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper,
-				  int preferred_bpp)
+static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper,
+					 int preferred_bpp)
 {
 	int new_fb = 0;
 	int crtc_count = 0;
@@ -870,7 +870,6 @@
 
 	return 0;
 }
-EXPORT_SYMBOL(drm_fb_helper_single_fb_probe);
 
 void drm_fb_helper_fill_fix(struct fb_info *info, uint32_t pitch,
 			    uint32_t depth)