[BUG] Virtual grains are not properly detected on Nutanix AHV

[meaksh]

Description
The virtual grains are not correctly detected on VMs running on Nutanix AHV:

# salt-call grains.items
[...]
virtual:
    physical

Setup
(Please provide relevant configs and/or SLS files (be sure to remove sensitive info. There is no general set-up of Salt.)

Please be as specific as possible and give set-up details.

• on-prem machine
• VM (Nutanix AHV)
• VM running on a cloud service, please be explicit and add details
• container (Kubernetes, Docker, containerd, etc. please specify)
• or a combination, please be explicit
• jails if it is FreeBSD
• classic packaging
• onedir packaging
• used bootstrap to install

Steps to Reproduce the behavior
Execute:

# salt-call grains.items
[...]
virtual:
    physical

Expected behavior
A clear and concise description of what you expected to happen.

# salt-call grains.items
[...]
virtual:
    kvm
virtual_subtype:
    Nutanix AHV

Screenshots
N/A

Versions Report

salt --versions-report

(Provided by running salt --versions-report. Please also mention any differences in master/minion versions.)

PASTE HERE

Additional context
Add any other context about the problem here.