Don't pass ATTEST_KEY for symmetric key generation am: 6d825fb225

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/3375315

Change-Id: Ie4efca867525f393d39cfa0c29904034ce9bac26
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>