drm/kms/fb: use slow work mechanism for normal hotplug also.

a) slow work is always used now for any fbcon hotplug, as its not
   a fast task and is more suited to being ran under slow work.

b) attempt to not do any fbdev changes when X is running as we'll
   just mess it up. This hooks set_par to hopefully do the changes
   once X hands control to fbdev.

This also adds the nouveau/intel hotplug support.

Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 9ffb9f2..11fce59 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -228,4 +228,6 @@
 				   struct drm_file *file_priv);
 extern int intel_overlay_attrs(struct drm_device *dev, void *data,
 			       struct drm_file *file_priv);
+
+void intelfb_hotplug(struct drm_device *dev, bool polled);
 #endif /* __INTEL_DRV_H__ */