SUNRPC: Convert rpc_clnt->cl_users to a kref

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/net/sunrpc/rpc_pipe.c b/net/sunrpc/rpc_pipe.c
index 5887457..826190d 100644
--- a/net/sunrpc/rpc_pipe.c
+++ b/net/sunrpc/rpc_pipe.c
@@ -344,7 +344,7 @@
 		mutex_lock(&inode->i_mutex);
 		clnt = RPC_I(inode)->private;
 		if (clnt) {
-			atomic_inc(&clnt->cl_users);
+			kref_get(&clnt->cl_kref);
 			m->private = clnt;
 		} else {
 			single_release(inode, file);