IB/core: Fix error return code in add_port()

Fix to return -ENOMEM in the add_port() error handling case instead of
0, as done elsewhere in this function.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Roland Dreier <roland@purestorage.com>
diff --git a/drivers/infiniband/core/sysfs.c b/drivers/infiniband/core/sysfs.c
index 246fdc1..d9b78c4 100644
--- a/drivers/infiniband/core/sysfs.c
+++ b/drivers/infiniband/core/sysfs.c
@@ -545,8 +545,10 @@
 
 	p->gid_group.name  = "gids";
 	p->gid_group.attrs = alloc_group_attrs(show_port_gid, attr.gid_tbl_len);
-	if (!p->gid_group.attrs)
+	if (!p->gid_group.attrs) {
+		ret = -ENOMEM;
 		goto err_remove_pma;
+	}
 
 	ret = sysfs_create_group(&p->kobj, &p->gid_group);
 	if (ret)
@@ -555,8 +557,10 @@
 	p->pkey_group.name  = "pkeys";
 	p->pkey_group.attrs = alloc_group_attrs(show_port_pkey,
 						attr.pkey_tbl_len);
-	if (!p->pkey_group.attrs)
+	if (!p->pkey_group.attrs) {
+		ret = -ENOMEM;
 		goto err_remove_gid;
+	}
 
 	ret = sysfs_create_group(&p->kobj, &p->pkey_group);
 	if (ret)