Change archive-update.test to create a new file on the fly.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186206 91177308-0d34-0410-b5e6-96231b3b80d8
R600: Reapply testcase from r186178, the big endian issue should be fixed by r186196.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186209 91177308-0d34-0410-b5e6-96231b3b80d8