Cross-SIM reg: check data is on other slot

- For determining CST availability, IWLAN would check if the
current sub was the nDDS, and assume that the data PDN was always on the DDS.
- This cross-SIM condition is relaxed so that either sub can establish
CST, as long as the active data PDN is on the other sub.
- This will allow the DDS to establish cross-SIM over nDDS in some
  cases: for eg.  when DDS is OOS and nDDS temporarily holds the data PDN.
- Clean up of IwlanNetworkServiceTests.

Bug: 249609998
Test: Live test on P10. UTs updated:
IwlanDataServiceTests#testIwlanSetupDataCallFailsWithCellularAndCstDisabled
IwlanDataServiceTests#testIwlanSetupDataCallFailsWithCellularOnSameSubAndCstEnabled
IwlanDataServiceTests#testIwlanSetupDataCallSucceedsWithCellularOnDifferentSubAndCstEnabled
IwlanNetworkServiceTests#testNetworkRegistrationInfoSearchingForCellularAndCstDisabled
IwlanNetworkServiceTests#testNetworkRegistrationInfoSearchingForCellularOnSameSubAndCstEnabled
IwlanNetworkServiceTests#testNetworkRegistrationInfoHomeForCellularOnDifferentSubAndCstEnabled

Change-Id: I471914c79ff07d5c25499b8953c6ec7cde67fd7d
5 files changed