Optimize calls to TelephonyManager to check for privileged apps

Calling into TelephonyManager each of hundreds of apps to check
if the app is carrier privileged was very expensive, especially
when there aren't even any carrier access rules specified. This
change fetches all the carrier privileged apps in one call,
reducing the number of IPC calls to the radio process and checks
the package names locally.

If the carrier rules change or packages are modified, the list
will be computed and fetched again.

Other optimizations in Telephony help speed up the individual calls
to check if a package is privileged, as well.

Bug: 27271861
Change-Id: I5a77b6da4f2cdc603d2a73bd8569c5c38f06b42d