Add ignored hidden_api.split_packages/package_prefixes properties

Allow modules upstream to make use of these properties despite
sc-mainline-prod not supporting them.

Bug: 194063708
Test: m nothing
Merged-In: If2f90cfc41b6fff9fa4ac8b9d4973110938b9392
Change-Id: I85c13c115ffafc797566ced6c3672a9b0dca59b1