dma-buf/sw_sync: remove pointless enable_signaling implementation

Just returning true here is a no-op, remove the optional callback.

Signed-off-by: Christian König <[e-mail]>
Reviewed-by: Simona Vetter <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/dma-buf/sw_sync.c

···
 	return !__dma_fence_is_later(fence->seqno, parent->value, fence->ops);
 }
 
-static bool timeline_fence_enable_signaling(struct dma_fence *fence)
-{
-	return true;
-}
-
 static void timeline_fence_value_str(struct dma_fence *fence,
 				    char *str, int size)
 {
···
 static const struct dma_fence_ops timeline_fence_ops = {
 	.get_driver_name = timeline_fence_get_driver_name,
 	.get_timeline_name = timeline_fence_get_timeline_name,
-	.enable_signaling = timeline_fence_enable_signaling,
 	.signaled = timeline_fence_signaled,
 	.release = timeline_fence_release,
 	.fence_value_str = timeline_fence_value_str,