SUNRPC: Eliminate task->tk_xprt accesses that bypass rcu_dereference()

tk_xprt is just a shortcut for tk_client->cl_xprt, however cl_xprt is
defined as an __rcu variable. Replace dereferences of tk_xprt with
non-rcu dereferences where it is safe to do so.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index 68b0a81..2583890 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -770,7 +770,7 @@
 		goto out_release;
 	if (req->rq_bytes_sent == req->rq_snd_buf.len)
 		goto out_release;
-	set_bit(XPRT_CLOSE_WAIT, &task->tk_xprt->state);
+	set_bit(XPRT_CLOSE_WAIT, &xprt->state);
 out_release:
 	xprt_release_xprt(xprt, task);
 }