radeon: add support for vblank on crtc2

This adds support for CRTC2 vblank on radeon similiar to the i915.

Signed-off-by: Dave Airlie <airlied@linux.ie>
diff --git a/drivers/char/drm/radeon_drv.c b/drivers/char/drm/radeon_drv.c
index 2eb652e..349ac3d 100644
--- a/drivers/char/drm/radeon_drv.c
+++ b/drivers/char/drm/radeon_drv.c
@@ -60,7 +60,7 @@
 	.driver_features =
 	    DRIVER_USE_AGP | DRIVER_USE_MTRR | DRIVER_PCI_DMA | DRIVER_SG |
 	    DRIVER_HAVE_IRQ | DRIVER_HAVE_DMA | DRIVER_IRQ_SHARED |
-	    DRIVER_IRQ_VBL,
+	    DRIVER_IRQ_VBL | DRIVER_IRQ_VBL2,
 	.dev_priv_size = sizeof(drm_radeon_buf_priv_t),
 	.load = radeon_driver_load,
 	.firstopen = radeon_driver_firstopen,
@@ -70,6 +70,7 @@
 	.lastclose = radeon_driver_lastclose,
 	.unload = radeon_driver_unload,
 	.vblank_wait = radeon_driver_vblank_wait,
+	.vblank_wait2 = radeon_driver_vblank_wait2,
 	.dri_library_name = dri_library_name,
 	.irq_preinstall = radeon_driver_irq_preinstall,
 	.irq_postinstall = radeon_driver_irq_postinstall,