drm: move drm vblank initialization/cleanup to driver load/unload

drm vblank initialization keeps track of the changes in driver-supplied
frame counts across vt switch and mode setting, but only if you let it by
not tearing down the drm vblank structure.

Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 15c8dab..1e787f8 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -94,7 +94,7 @@
 	}
 }
 
-static void drm_vblank_cleanup(struct drm_device *dev)
+void drm_vblank_cleanup(struct drm_device *dev)
 {
 	/* Bail if the driver didn't call drm_vblank_init() */
 	if (dev->num_crtcs == 0)
@@ -278,8 +278,6 @@
 
 	free_irq(dev->pdev->irq, dev);
 
-	drm_vblank_cleanup(dev);
-
 	return 0;
 }
 EXPORT_SYMBOL(drm_irq_uninstall);