SUNRPC: allow the caller of rpc_run_task to preallocate the struct rpc_task

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/include/linux/sunrpc/sched.h b/include/linux/sunrpc/sched.h
index c9444fd..60a05c7 100644
--- a/include/linux/sunrpc/sched.h
+++ b/include/linux/sunrpc/sched.h
@@ -118,6 +118,7 @@
 };
 
 struct rpc_task_setup {
+	struct rpc_task *task;
 	struct rpc_clnt *rpc_client;
 	const struct rpc_message *rpc_message;
 	const struct rpc_call_ops *callback_ops;