Clean up unused indication update mode definition in TelephonyManager

INDICATION_UPDATE_MODE_NORMAL and
INDICATION_UPDATE_MODE_IGNORE_SCREEN_OFF was used to set the indication
update mode. But all the usage has been removed, the definitions become
orphan.

Bug: 174614001
Test: m -j
Change-Id: I1ddf89bae8d7a477ae3a521f052bc921cf3ee5ae