Fail an installation if master node count is more than 3

1. Proposed title of this feature request
   Openshift cluster installation should fail if user is trying to keep master nodes higher han 3 in an Openshift cluster.
2. What is the nature and description of the request?
   5 master nodes are currently unsupported. However some customers mistakenly mention master node count as 5 in install-config.yml and the installation process goes on with unsupported master value and create 5 master nodes. Installation should fail if master node count mentioned in install-config.yml is unsupported.
3. . Why does the customer need this? (List the business requirements here)
   To avoid any unsupported configuration and Openshift installer should be able to  disallow any such configuration in install-config.yml
4. . List any affected packages or components

            Installation