Correct 2Degrees APN

Per https://jira.cyanogenmod.org/browse/CYAN-1509 2Degrees
default APN is incorrect. Delete 2 extra APN configs to
be in line with http://www.2degreesmobile.co.nz/android-settings.

Change-Id: I00ad879c2752e73d31850bd36c1e0337a7797796