Update recommended policy to add required IAM permissions (#127)

Issue #2164, if available:
aws-controllers-k8s/community#2164

Description of changes:
Update recommended policy to add the following IAM permissions:
- iam:ListAttachedRolePolicies
- ec2:DescribeSubnets

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

Author: xiangyanw

config/iam/recommended-inline-policy

@@ -6,7 +6,9 @@
             "Action": [
                 "eks:*",
                 "iam:GetRole",
-                "iam:PassRole"
+                "iam:PassRole",
+                "iam:ListAttachedRolePolicies",
+                "ec2:DescribeSubnets"
             ],
             "Resource": "*"
         }