NFSv4: Remove the BUG_ON() from nfs4_get_lease_time_prepare()...

An EAGAIN return value would be unexpected, but there is no reason to
BUG...

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 5eec442..14d86ef 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -5581,8 +5581,8 @@
 				   &data->args->la_seq_args,
 				   &data->res->lr_seq_res, task);
 
-	BUG_ON(ret == -EAGAIN);
-	rpc_call_start(task);
+	if (ret != -EAGAIN)
+		rpc_call_start(task);
 	dprintk("<-- %s\n", __func__);
 }