Add ASan metadata globals to @llvm.compiler.used under COFF

Summary:
This matches ELF.

This makes the number of ASan failures under the new pass manager on
Windows go from 18 to 1.

Under the old pass manager, the ASan module pass was one of the very
last things run, so these globals didn't get removed due to GlobalOpt.
But with the NPM the ASan module pass that adds these globals are run
much earlier in the pipeline and GlobalOpt ends up removing them.

Reviewers: vitalybuka, hans

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D81175