Service state not updated for manual IP addressing

On TX2 the service state is not reported when the interface is ready.

With the interface ready and in the network, when disconnecting the network cable I get these state changes:

enp1s0 state changed: Configuration
enp1s0 state changed: Disconnect
enp1s0 state changed: Idle

When reconnecting the cable, the state does not change so it's not possible to detect the interface is ready. Connmanctl reports the the interface/service ready ('R').

With DHCP method, the state is reported correctly.

Steps to reproduce:

1. Set static IP
2. TX2 Connect to the network
3. Disconnect the network cable
4. Reconnect the network cable