docs: document bridge mode option

Signed-off-by: Michael Zimmermann <[email protected]>

docs/source/markdown/podman-network-create.1.md

@@ -118,6 +118,9 @@ Additionally the `bridge` driver supports the following options:
 - `com.docker.network.bridge.name`: This option assigns the given name to the created Linux Bridge
 - `com.docker.network.driver.mtu`: Sets the Maximum Transmission Unit (MTU) and takes an integer value.
 - `vrf`: This option assigns a VRF to the bridge interface. It accepts the name of the VRF and defaults to none. Can only be used with the Netavark network backend.
+- `mode`: This option sets the specified bridge mode on the interface. Defaults to `managed`. Supported values:
+  - `managed`: Podman creates and deleted the bridge. It will also setup sysctls and firewall rules for it.
+  - `unmanaged`: Podman uses an existing bridge. It must exist by the time you want to start a container which uses the network.
 
 The `macvlan` and `ipvlan` driver support the following options: