drm/nouveau: fix unconditional return waiting on memory

Typo in nv50_display_flip_wait allows page flipping to run ahead before
memory has time to settle.
Signed-off-by: NCalvin Owens <jcalvinowens@gmail.com>
Signed-off-by: NBen Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/nv50_display.c

@@ -479,7 +479,7 @@ nv50_display_flip_wait(void *data)
 {
 	struct nv50_display_flip *flip = data;
 	if (nouveau_bo_rd32(flip->disp->sync, flip->chan->addr / 4) ==
-					      flip->chan->data);
+					      flip->chan->data)
 		return true;
 	usleep_range(1, 2);
 	return false;