As per the RFE 3104, 

The limitation to the use of mac address while creating VMs on vsphere infra was removed in  RHOCP 4.14 version and above.

In the documentation of RHOCP 4.14, the section of mac address requirement was removed which was earlier present in below version.

4.14:
https://docs.openshift.com/container-platform/4.10/installing/installing_vsphere/installing-vsphere-network-customizations.html

4.13: 
https://docs.openshift.com/container-platform/4.13/installing/installing_vsphere/installing-vsphere-network-customizations.html

It is being observed that the changes made to 4.14 documentation is not included in later version 4.15 and above.

Need to fix them in following documentation as well.

https://docs.openshift.com/container-platform/4.15/installing/installing_vsphere/upi/upi-vsphere-installation-reqs.html
https://docs.openshift.com/container-platform/4.16/installing/installing_vsphere/upi/upi-vsphere-installation-reqs.html
https://docs.openshift.com/container-platform/4.17/installing/installing_vsphere/upi/upi-vsphere-installation-reqs.html

4.17    

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