Update RadioAccessFamily#compare in E911

The E911 phone selection logic uses a two-phase approach to pick
a phone based on the RAT type. This CL migrates those two stages
into the RadioAccessFamly class and removes references to
TelephonyManager#NETWORK_CLASS_ constants that are being removed
at the same time.

Bug: 128572818
Test: compilation
Change-Id: I11e3319e3f3351cc17f92260b4389e23bb016698
1 file changed