[fuzzer][test] Disable noasan-strncmp test for AArch64

This test fails on several aarch64 bots
  clang-aarch64-lld-2stage ( https://lab.llvm.org/buildbot/#/builders/185/builds/3525 )
  clang-aarch64-full-2stage ( https://lab.llvm.org/buildbot/#/builders/179/builds/5904 )
  clang-aarch64-sve-vla ( https://lab.llvm.org/buildbot/#/builders/197/builds/4519 )
Disable it while this is analyzed.

Reviewed By: DavidSpickett

Differential Revision: https://reviews.llvm.org/D148332