SUNRPC: Set SOFTCONN when destroying GSS contexts

Move the RPC_TASK_SOFTCONN flag into rpc_call_null_helper(). The
only minor behavior change is that it is now also set when
destroying GSS contexts.

This gives a better guarantee that gss_send_destroy_context() will
not hang for long if a connection cannot be established.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

net/sunrpc/clnt.c

@@ -2752,7 +2752,8 @@ struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt,
 		.rpc_op_cred = cred,
 		.callback_ops = (ops != NULL) ? ops : &rpc_default_ops,
 		.callback_data = data,
-		.flags = flags | RPC_TASK_SOFT | RPC_TASK_NULLCREDS,
+		.flags = flags | RPC_TASK_SOFT | RPC_TASK_SOFTCONN |
+			 RPC_TASK_NULLCREDS,
 	};
 
 	return rpc_run_task(&task_setup_data);
@@ -2815,8 +2816,7 @@ int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt,
 		goto success;
 	}
 
-	task = rpc_call_null_helper(clnt, xprt, NULL,
-			RPC_TASK_SOFTCONN|RPC_TASK_ASYNC,
+	task = rpc_call_null_helper(clnt, xprt, NULL, RPC_TASK_ASYNC,
 			&rpc_cb_add_xprt_call_ops, data);
 
 	rpc_put_task(task);
@@ -2859,8 +2859,7 @@ int rpc_clnt_setup_test_and_add_xprt(struct rpc_clnt *clnt,
 		goto out_err;
 
 	/* Test the connection */
-	task = rpc_call_null_helper(clnt, xprt, NULL, RPC_TASK_SOFTCONN,
-				    NULL, NULL);
+	task = rpc_call_null_helper(clnt, xprt, NULL, 0, NULL, NULL);
 	if (IS_ERR(task)) {
 		status = PTR_ERR(task);
 		goto out_err;