[ Merge of http://go/wvgerrit/151518 ]
Extended the CDM layer to report OEMCrypto's production readiness
via string property query.
If OEMCrypto implementents OEMCrypto_ProductionReady(), then the
reported readiness by the CDM will report "True" or "False".
If OEMCrypto does not implement OEMCrypto_ProductionReady() then no
level of readiness is assumed, and the CDM will report "Unknown".
Bug: 231655151
Test: run_prov30_tests and request_license_test
Change-Id: I6afe481ef00ac129d02b004eca89a65810bfbff8
cd5afa88a6