Catch failed connection due to a bad region in ec2_scaling_policy

Fixes #7505

cloud/ec2_asg

@@ -216,6 +216,8 @@ def main():
     region, ec2_url, aws_connect_params = get_aws_connection_info(module)
     try:
         connection = connect_to_aws(boto.ec2.autoscale, region, **aws_connect_params)
+        if not connection:
+            module.fail_json(msg="failed to connect to AWS for the given region: %s" % str(region))
     except boto.exception.NoAuthHandlerFound, e:
         module.fail_json(msg=str(e))