video/fb: Propagate error code from failing to unregister conflicting fb

If we fail to remove a conflicting fb driver, we need to abort the
loading of the second driver to avoid likely kernel panics.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: linux-fbdev@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/include/linux/fb.h b/include/linux/fb.h
index 70c4836..fe6ac95 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -613,8 +613,8 @@
 extern int register_framebuffer(struct fb_info *fb_info);
 extern int unregister_framebuffer(struct fb_info *fb_info);
 extern int unlink_framebuffer(struct fb_info *fb_info);
-extern void remove_conflicting_framebuffers(struct apertures_struct *a,
-				const char *name, bool primary);
+extern int remove_conflicting_framebuffers(struct apertures_struct *a,
+					   const char *name, bool primary);
 extern int fb_prepare_logo(struct fb_info *fb_info, int rotate);
 extern int fb_show_logo(struct fb_info *fb_info, int rotate);
 extern char* fb_get_buffer_offset(struct fb_info *info, struct fb_pixmap *buf, u32 size);