pylint: ensure variables are initialized

pylint doesn't know that some functions may terminate execution, like,
AnsibleModule's fail_json, and assume that, depending on the code path,
some variables may not be initialized when used.

This change ensure that variables are always initialized independent of
the code path.

plugins/modules/ipadnsrecord.py

@@ -1605,6 +1605,8 @@ def main():
 
             res_find = find_dnsrecord(ansible_module, zone_name, name)
 
+            cmds = []
+
             if state == 'present':
                 cmds = define_commands_for_present_state(
                     ansible_module, zone_name, entry, res_find)