Revert "Hash ICC ID used in the notification tag for voicemail notifications."

This reverts commit 1fd917b3.

Reason for revert:

Change-Id: Ibf3c3e3c0530b8437bacc570aeae15ba2c5881da
Merged-In: Ibf3c3e3c0530b8437bacc570aeae15ba2c5881da
DroidMonitor: DroidMonitor-triggered revert due to breakage https://android-build.googleplex.com/builds/quarterdeck?branch=git_sc-dev&target=sdk_phone_armv7-win_sdk&lkgb=7899854&lkbb=7900105&fkbb=7900056,
bug b/205776652