drm/exynos: pass the correct pipe number

Instead of giving -1 to as arg to  drm_send_vblank_event() pass the
correct pipe number to it.
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Reviewed-by: Joonyoung Shim <jy0922.shim@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

drivers/gpu/drm/exynos/exynos_drm_crtc.c

@@ -205,7 +205,7 @@ void exynos_drm_crtc_finish_pageflip(struct drm_device *dev, int pipe)
 	spin_lock_irqsave(&dev->event_lock, flags);
 	if (exynos_crtc->event) {
 
-		drm_send_vblank_event(dev, -1, exynos_crtc->event);
+		drm_send_vblank_event(dev, pipe, exynos_crtc->event);
 		drm_vblank_put(dev, pipe);
 		wake_up(&exynos_crtc->pending_flip_queue);