Teach `-fsanitize=fuzzer` to respect `-static` and `-static-libstdc++` when...

Teach `-fsanitize=fuzzer` to respect `-static` and `-static-libstdc++` when adding C++ standard libraries.

Summary:
Makes linking the sanitizers follow the same logic as the rest of the
driver with respect to the static linking strategy for the C++ standard
library.

Subscribers: mcrosier, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D80488