Merge "KeyMint VTS: don't combine ATTEST_KEY with SIGN" am: 4f51da1c9e am: bc899371f4 am: e230fd076e

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/1877245

Change-Id: I770451df7ead1e13e7a03a013b8d9205aabfb61f