drm/nvd0/disp: remove unnecessary sync from flip_next

This shouldn't be necessary, I believe this is just a bit of missed debug
code that got left over somehow.

Causes flips to be always synced to vblank, regardless of swap interval,
which we don't want..
Signed-off-by: NBen Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/nvd0_display.c

@@ -284,8 +284,6 @@ nvd0_display_flip_next(struct drm_crtc *crtc, struct drm_framebuffer *fb,
 	u32 *push;
 	int ret;
 
-	evo_sync(crtc->dev, EVO_MASTER);
-
 	swap_interval <<= 4;
 	if (swap_interval == 0)
 		swap_interval |= 0x100;