Map new WFC related ImsReasonInfo codes to disconnect causes.

Map CODE_EMERGENCY_CALL_OVER_WFC_NOT_AVAILABLE and
CODE_WFC_SERVICE_NOT_AVAILABLE_IN_THIS_LOCATION to the corresponding
disconnect cause in Telephony.
Make reason string matching case insensitive.

Bug: 128993720
Test: Unit tests added to confirm remapping.
Change-Id: I2ae48a78c10ed6ade2117c89d9298f479c548bd4