Add DNSMASQ_LISTENING=bind to README.md

Signed-off-by: Jan Noormann <[email protected]>

README.md

@@ -128,7 +128,7 @@ There are other environment variables if you want to customize various things in
 | Variable | Default | Value | Description |
 | -------- | ------- | ----- | ---------- |
 | `INTERFACE` | unset | `<NIC>` | The default works fine with our basic example docker run commands.  If you're trying to use DHCP with `--net host` mode then you may have to customize this or DNSMASQ_LISTENING.
-| `DNSMASQ_LISTENING` | unset | `<local\|all\|single>` | `local` listens on all local subnets, `all` permits listening on internet origin subnets in addition to local, `single` listens only on the interface specified.
+| `DNSMASQ_LISTENING` | unset | `<local\|all\|single\|bind>` | `local` binds any interface and listens on all local subnets, `all` binds any interface and permits listening on internet origin subnets in addition to local, `single` binds any interface and listens only on the interface specified, `bind` binds only on the interface specified.
 | `WEB_PORT` | unset | `<PORT>` | **This will break the 'webpage blocked' functionality of Pi-hole** however it may help advanced setups like those running synology or `--net=host` docker argument.  This guide explains how to restore webpage blocked functionality using a linux router DNAT rule: [Alternative Synology installation method](https://discourse.pi-hole.net/t/alternative-synology-installation-method/5454?u=diginc)
 | `WEB_BIND_ADDR` | unset | `<IP>` | Lighttpd's bind address. If left unset lighttpd will bind to every interface, except when running in host networking mode where it will use `FTLCONF_LOCAL_IPV4` instead.
 | `SKIPGRAVITYONBOOT` | unset | `<unset\|1>` | Use this option to skip updating the Gravity Database when booting up the container.  By default this environment variable is not set so the Gravity Database will be updated when the container starts up.  Setting this environment variable to 1 (or anything) will cause the Gravity Database to not be updated when container starts up.