Description of problem:

The issue with standard Redfish virtual media boot has
been fixed now. Update to restrict use of redfish-virtual-media
based on iDRAC firmware version.

Version-Release number of selected component (if applicable):

How reproducible:
Everytime

Steps to Reproduce:
1. Use redfish-virtual-media as boot interface

Actual results:
Ironic fails with error saying that can't use redfish-virtual-media with iDRAC

Expected results:
1) Ironic continues and successfully boots from virtual media when using iDRAC firmware 6.00.00.00 or above
2) Ironic still fails to boot virtual media when using iDRAC firmware before 6.00.00.00

Additional info:
This is to backport to 4.10.