Fix libvirt/images path

Has to match how it's defined in the order above.

dotfiles/i3status.conf

@@ -53,7 +53,7 @@ tztime local {
     format = "%Y-%m-%d %H:%M"
 }
 
-disk "/var/lib/libvirt/images/" {
+disk "/var/lib/libvirt/images" {
     format = "virt:%avail"
     threshold_type = "gbytes_avail"
     low_threshold = 2