Enable ASAN on NetBSD

Summary:
This enables also static runtime option.

Sponsored by <The NetBSD Foundation>

Reviewers: joerg, vitalybuka, filcab, kcc, fjricci

Reviewed By: vitalybuka

Subscribers: mgorny, llvm-commits, #sanitizers

Tags: #sanitizers

Differential Revision: https://reviews.llvm.org/D36490

llvm-svn: 310651