Replace hidden CM#isNetworkSupported() usage

It's a refactor work for connectivity mainline module. The
hidden methods access is no longer allowed, so the usage for
isNetworkSupported() should be replaced. Settings use it to
check if device support telephony, wifi or ethernet service.
There are alternative methods to check if device supports such
features. Replace as it is.

Bug: 172183305
Test: m ; make RunSettingsRoboTests
Change-Id: I8f1d11558b1be575a0777ed195abe027e838cb74
Merged-In: I8f1d11558b1be575a0777ed195abe027e838cb74