Respect description option and delete security group rules first

The description option of security group rules will now be used properly
when creating new rules.

Security group rules have to be deleted first before new ones get
created, because if one changes one rule attribute such as its
description, then the old rule must be deleted before recreating it,
as rules cannot be updated.

Story: 2010605
Task: 47486

Change-Id: I75b900e6675f7ec33532089738a6c2bfc10a898b

plugins/modules/security_group_rule.py

@@ -308,7 +308,8 @@ class SecurityGroupRuleModule(OpenStackModule):
     def _define_prototype(self):
         filters = {}
         prototype = dict((k, self.params[k])
-                         for k in ['direction', 'remote_ip_prefix']
+                         for k in ['description', 'direction',
+                                   'remote_ip_prefix']
                          if self.params[k] is not None)
 
         # When remote_ip_prefix is missing a netmask, then Neutron will add