vga_switcheroo: add reprobe hook for fbcon to recheck connected outputs.

This adds a hook after the mux is switched for the driver to reprobe
the connected outputs.

Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/nouveau/nouveau_state.c b/drivers/gpu/drm/nouveau/nouveau_state.c
index db4b410..1b87eee 100644
--- a/drivers/gpu/drm/nouveau/nouveau_state.c
+++ b/drivers/gpu/drm/nouveau/nouveau_state.c
@@ -605,6 +605,12 @@
 	}
 }
 
+static void nouveau_switcheroo_reprobe(struct pci_dev *pdev)
+{
+	struct drm_device *dev = pci_get_drvdata(pdev);
+	nouveau_fbcon_output_poll_changed(dev);
+}
+
 static bool nouveau_switcheroo_can_switch(struct pci_dev *pdev)
 {
 	struct drm_device *dev = pci_get_drvdata(pdev);
@@ -625,6 +631,7 @@
 
 	vga_client_register(dev->pdev, dev, NULL, nouveau_vga_set_decode);
 	vga_switcheroo_register_client(dev->pdev, nouveau_switcheroo_set_state,
+				       nouveau_switcheroo_reprobe,
 				       nouveau_switcheroo_can_switch);
 
 	/* Initialise internal driver API hooks */