Add braces {} for arms of if/for statement

Signed-off-by: Zhang Han <zhanghan64@huawei.com>
Message-Id: <20201228071129.24563-5-zhanghan64@huawei.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>