SysUI: add a flag to control location indicators behavior.

Under the new flag, the location indicators will display when either
location indicators flag is enabled, or when permission hub feature is
enabled.

Bug: 171057373
Test: atest PrivacyItemControllerFlagsTest
Test: Manual
Change-Id: I628ced3108f4844444915e10a7e0bfbb0a9b8309