iwd.service: Add CAP_NET_BIND_SERVICE

This fixes an issue where the udp port was not being opened due to a
permission denied error. The result of this was the dhcp client would
fail to send the renewal request and so the dhcp lease would expire.

The addition of the CAP_NET_BIND_SERVICE capability allows the service
to open sockets in the restricted port range (<1024) which is required
for dhcp.

src/iwd.service.in

@@ -11,7 +11,7 @@ ExecStart=@libexecdir@/iwd
 NotifyAccess=main
 LimitNPROC=1
 Restart=on-failure
-CapabilityBoundingSet=CAP_NET_ADMIN CAP_NET_RAW
+CapabilityBoundingSet=CAP_NET_ADMIN CAP_NET_RAW CAP_NET_BIND_SERVICE
 PrivateTmp=true
 NoNewPrivileges=true
 DevicePolicy=closed