virt-install: Use rhel7.6
Fixes a virt-install deprecation warning about just saying `7`.
@@ -207,7 +207,7 @@ try:
location_arg += ",kernel=isolinux/vmlinuz,initrd=isolinux/initrd.img"
vinstall_args.extend(["--wait={}".format(args.wait), "--noreboot", "--nographics",
"--memory={}".format(args.memory), get_libvirt_smp_arg(),
- "--os-variant=rhel7", "--rng=/dev/urandom",
+ "--os-variant=rhel7.6", "--rng=/dev/urandom",
"--cpu=host-passthrough",
"--check", "path_in_use=off",
"--network=user", # user mode networking
