Add ims registration status

Display "IMS registration state" in Status menu. Introduce carrier
config to enable/disable the feature for customization. Since some
carriers require, this feature is necessary.

Test: manual Checked "IMS registration state" in Status menu
Bug: 28806101
Merged-In: I6c452c512f03cf41704b91331e44141ed3050cf9
Change-Id: I6c452c512f03cf41704b91331e44141ed3050cf9
3 files changed