Fixed empty phone number

For getting phone number from UICC, when getLine1Number is not available,
fallback to phone number stored in subscription info.

Fix: 302437869
Flag: uicc_phone_number_fix
Test: atest SubscriptionManagerServiceTest
Test: Basic telephony functionality tests
Change-Id: I0e5a9db89fbe94e4f08928da2cb98230c3655128