sysfs: fix sysfs lockdep warning in infiniband code

This fixes a sysfs lockdep warning in the infiniband code.

Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/infiniband/core/sysfs.c

@@ -461,6 +461,7 @@ alloc_group_attrs(ssize_t (*show)(struct ib_port *,
 		element->attr.attr.mode  = S_IRUGO;
 		element->attr.show       = show;
 		element->index		 = i;
+		sysfs_attr_init(&element->attr.attr);
 
 		tab_attr[i] = &element->attr.attr;
 	}