Add -broadcast flag to DHCP plugin documentation

Signed-off-by: Micah Hausler <[email protected]>

content/plugins/ipam/dhcp.md

@@ -25,7 +25,12 @@ $ ./dhcp daemon
 
 If given `-pidfile <path>` arguments after 'daemon', the dhcp plugin will write
 its PID to the given file.
-If given `-hostprefix <prefix>` arguments after 'daemon', the dhcp plugin will use this prefix for DHCP socket as `<prefix>/run/cni/dhcp.sock`. You can use this prefix for references to the host filesystem, e.g. to access netns and the unix socket.
+If given `-hostprefix <prefix>` arguments after 'daemon', the dhcp plugin will
+use this prefix for DHCP socket as `<prefix>/run/cni/dhcp.sock`. You can use
+this prefix for references to the host filesystem, e.g. to access netns and the
+unix socket.
+If given `-broadcast=true` argument after 'daemon', the dhcp plugin will
+enable the broadcast flag on DHCP packets.
 
 Alternatively, you can use systemd socket activation protocol.
 Be sure that the .socket file uses /run/cni/dhcp.sock as the socket path.