[nolibc] Add a test case for Linux/x86_64.

Differential Revision: http://llvm-reviews.chandlerc.com/D873

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@182770 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed