Minor fixes for os_security_group_rule module

Was not able to use this module as it was.  The changes submitted
resolved the issues I ran into in order to get it working.

lib/ansible/modules/cloud/openstack/os_security_group_rule.py

@@ -153,4 +153,5 @@ def main():
 # this is magic, see lib/ansible/module_common.py
 from ansible.module_utils.basic import *
 from ansible.module_utils.openstack import *
+
 main()