SUNRPC: Reduce asynchronous RPC task stack usage

We should just farm out asynchronous RPC tasks immediately to rpciod...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

net/sunrpc/sched.c

@@ -699,7 +699,8 @@ static void __rpc_execute(struct rpc_task *task)
 void rpc_execute(struct rpc_task *task)
 {
 	rpc_set_active(task);
-	rpc_set_running(task);
+	rpc_make_runnable(task);
+	if (!RPC_IS_ASYNC(task))
 		__rpc_execute(task);
 }