Merge "Add getKeyCharacteristics stub to KeyMint" am: e50e545fd0 am: 3636cc0ad7 am: 8f8579e09d am: c3b1f2d0e6

Original change: https://android-review.googlesource.com/c/platform/system/keymaster/+/1691318

Change-Id: I53fa1887f3fffaa8b6d88d6fb04eaa372f4cdd68