[test/gold] Add gold test subdirectory tests needing v1.12 (or higher)

Summary:
As discussed in the review for D22677, added a subdirectory to
enable tests that require at least version 1.12 of gold.

Add an initial test requiring this version.

Reviewers: davidxl, mehdi_amini

Subscribers: llvm-commits, mehdi_amini

Differential Revision: https://reviews.llvm.org/D22827

llvm-svn: 276860