[1.8b1 devices] Can't add a device that has IP address that it is within the wider range MAAS manages, but not within Dynamic/Static range MAAS manages

[Andres Rodriguez]

MAAS is configured to manage a network that's 10.245.0.10/18.

The Dynamic Range that MAAS manages is:
10.245.32.100 - 10.245.48.152

The Static Range that MAAS manages is:
10.245.0.152 - 10.245.4.255

I have a device that has a manually configured IP address of 10.245.0.150. When trying to add this device with this IP address, I'm not allow with 'Static IP' nor 'External IP'.

Given that 10.245.0.150 is part of the network that MAAS manages, I should be able to add a device and configured it with 'Static IP' address, specifying that the IP address I want to reserve is 10.245.0.150 and a hostmap should be automatically created. I think we need to validate that the IP address is not within the dynamic range, but rather, it is within the static range that MAAS manages, or the rest of the range.