Add missing hiddenapi product variables to Soong config

If72bd1c20b2014d0a3d400624d37fdb0a3052245 failed to propagate
PRODUCT_HIDDENAPI_STUBS* to Soong.

Bug: 124316921
Test: m out/soong/hiddenapi/hiddenapi-flags.csv, check previously
      blacklisted classes are now whitelisted.

Change-Id: I9b4a364654bad77b38ceb7062dafaeeab5f49517