Use 'virt' for latest

The versioned machine types can disappear in future versions of libvirt,
and the one in use 'virt-rhel8.2.0' is no longer available.
"virt" means "the latest version"

```
"msg": "libvirtError: unsupported configuration: Emulator
'/usr/libexec/qemu-kvm' does not support machine type 'virt-rhel8.2.0'"
```

Signed-off-by: Steeve Goveas <sgoveas@redhat.com>

vm-setup/roles/libvirt/templates/baremetalvm.xml.j2

@@ -22,7 +22,7 @@
   </os>
 {% else %}
 <os firmware='efi'>
-  <type arch='aarch64' machine='virt-rhel8.2.0'>hvm</type>
+  <type arch='aarch64' machine='virt'>hvm</type>
 </os>
 {% endif %}