Description of problem:
VMs are not getting IPv6 addresses in client but only shown in Azure Portal. Probable cause is:

1. cat /etc/cloud/cloud.cfg.d/91-azure_datasource.cfg
   datasource_list: [ Azure ]
   datasource:
   Azure:
   apply_network_config: False

After removing the last 3 lines in this file and do 'cloud-init clean' then reboot. IPv6 address is acquired fine.

Version-Release number of selected component (if applicable):
4.18.0-348.el8.x86_64 with cloud-init 21.1-7.el8 (RHEL 8.5 from Azure Marketplace)

How reproducible:
100%

Steps to Reproduce:
1. Create a VM from any RHEL images in Azure Marketplace (by far, 8.5, 8.6, 8.7... all have this same issue)

Actual results:
No IPv6 address acquired in client.

Expected results:
IPv6 address acquired normally.

Additional info:
1. Ubuntu images in Marketplace don't have above configuration or this issue.
2. Adding the above configuration in any of our images can reproduce this issue.
3. Previously QE has been testing without above configuration until recently. And no additional issues were observed before this.