Correct AttestKey test that checks Qualcomm's SPU waiver.

The test exempted KeyMint on the affected chips from having to implement
ATTEST_KEY if they have StrongBox in all Android releases from Android S
onwards, but the waiver was given only for Android S and T.  This CL
changes the test to reinstate the requirement after Android T.

Test: VtsAidlKeyMintTargetTest
Change-Id: I8481ae31de34aae220af7e7188632edcc2d391f0