Fix RKP support assumptions for keymint VTS

The support level for strongbox is different from the tee
implementation. Additionally, we were incorrectly checking the keymint
aidl version. KeyMint 1.0 supported ATTEST_KEY, so it's unclear why we
were ever checking for KeyMint 2.0.

Test: VtsAidlKeyMintTargetTest
Bug: 263844771
Change-Id: I750367902fec90204d71c1e158404b2421f9ad87