GsmCdmaPhone: Fix GSM SIM card ICCID on NV sub CDMA devices

The commit 94ae0fe7
("GsmCdmaPhone: Return dummy ICCID serial for NV sub")
broke the reported ICCID for GSM SIM cards when used
in global capable NV subscription CDMA devices.

GSM SIM ICCID shouldn't depend on the selected CDMA
subscription source in any way.

Change-Id: Ief48eba854f7c954eaa5132742fe00dc8aa9be13