[NFC][AIX]Disable failed tests due to aggressive byval alignment warning on AIX

These tests emit unexpected diagnostics on AIX because the byval alignment warning is emitted too aggressively. https://reviews.llvm.org/D118350 is supposed to provide a proper fix to the problem, but for the time being disable the tests to unblock.

Differential Revision: https://reviews.llvm.org/D118670