I have one instance of Piwik where the Location Provider: GeoIP (Php) is not showing up after updating to 3.0.0. It was active and in use before the update.
Here is how a fresh install looks like
Edit: GeoIP2 Plugin was installed afterwards because all other location provider options are not available at this server.
Edit 2: Have this problem actually on 2 separate servers.
@alorence Deactivating GeoIP2 (v0.1.2) solved the problem.
So this is another problem with the GeoIP2 Plugin.
It was missing the order key
'order' => 20
May be Piwik needs to check if a plugin doesn't have some required keys defined and let them use some other default value instead of letting it 'overwrite' a built in location provider.