Add interceptors for md2(3) from NetBSD

Summary:
MD2Init, MD2Update, MD2Final, MD2End, MD2File, MD2Data - calculates the
RSA Data Security, Inc., "MD2" message digest.

Add a dedicated test.

Reviewers: vitalybuka, joerg

Reviewed By: vitalybuka

Subscribers: kubamracek, llvm-commits, mgorny, #sanitizers

Tags: #sanitizers

Differential Revision: https://reviews.llvm.org/D55469

llvm-svn: 348744