sap_vm_provision: amend DNS var prefix

[sean-freeman]

sap_vm_provision: amend DNS var prefix

sap_vm_provision_aws_*
sap_vm_provision_ibmcloud_private_dns_*
sap_vm_provision_msazure_private_dns_*

[marcelmamula]

@sean-freeman Coming here from #55
I think we should focus on private DNS as you mentioned and AWS should reflect same. Trying to work on public side of things would be bit risky and counterproductive.

sap_vm_provision_aws_private_dns_*
sap_vm_provision_ibmcloud_private_dns_*
sap_vm_provision_msazure_private_dns_*
sap_vm_provision_gcp_private_dns_*

[sean-freeman]

@marcelmamula Agreed, scoping the Ansible Role to exclusive use of Private DNS functionality will be safer for everyone involved; the end-user can always target a DNS Service that has the option for Public Domain resolving or Corporate DNS Resolver interconnectivity etc etc and perform such tasks manually.