Remove broadcast of NETWORK_SET_TIMEZONE intent

android.intent.action.NETWORK_SET_TIMEZONE is not used by anything in
the platform so it can be removed. It was previously broadcast when
telephony made a time zone change, presumably as a way to coordinate
time zone detection logic if there were other, lower-priority detection
mechanisms on the device. The logic for time zone detection is now
centralized in the system server so coordination can be done more
directly when needed.

All the APK usages appear to be only manifest entries for
<protected-broadcast> in apps that don't send the intent themselves,
which doesn't make a lot of sense.

Note: There is a separate commit to remove the broadcast from the old
(disabled) NITZ logic.

Bug: 140712361
Test: treehugger
Change-Id: Iab629778e45815f4632359e90d920b7751c1a199