Merge pull request #3894 from gyliu513/kvm-driver

Highlight libvirtd for old distributions.

docs/drivers.md

@@ -36,21 +36,25 @@ sudo apt install libvirt-bin libvirt-daemon-system qemu-kvm
 sudo yum install libvirt-daemon-kvm qemu-kvm
 ```
 
-Enable,start, and verify the libvirtd service has started. 
+Enable,start, and verify the `libvirtd` service has started. 
 ```shell
 sudo systemctl enable libvirtd.service
 sudo systemctl start libvirtd.service
 sudo systemctl status libvirtd.service
 ```
 
 
-Then you will need to add yourself to libvirt group (older distributions may use libvirtd instead)
+Then you will need to add yourself to `libvirt` group (older distributions may use `libvirtd` instead)
 
-`sudo usermod -a -G libvirt $(whoami)`
+```shell
+sudo usermod -a -G libvirt $(whoami)
+```
 
 Then to join the group with your current user session:
 
-`newgrp libvirt`
+```shell
+newgrp libvirt
+```
 
 Now install the driver: