Keystore 2.0: Implement convertStorageKeyToEphemeral() in AndroidKeyMintDevice

Add the convertStorageKeyToEphemeral() function introduced into
IKeymintDevice for vold to get ephemeral per-boot keys from wrapped
storage keys. The function simply returns KM_ERROR_UNIMPLEMENTED.

Bug: 181806377
Bug: 181910578
Change-Id: I5c9f4cfaf05c768c0f768e4dca71c674a5d08aff
2 files changed