[clang] Disable check for system sanitizer blacklists files if...

[clang] Disable check for system sanitizer blacklists files if -fno-sanitizer-blacklist was specified

This is to avoid checking for the validity of a file that is not used.
This also contains a minor fix for the test, as the cfi sanitizer requires -flto and -fvisibility= arguments.

Differential Revision: https://reviews.llvm.org/D79043