Help DejaGnu avoid pipe-jam by producing less output from certain test cases.

Help DejaGnu avoid pipe-jam by producing less output from certain test cases.

When a test fails with more than a pipeful of output on stdout AND stderr, one
of the DejaGnu programs blocks. The problem can be avoided by redirecting
stdout to a file.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71919 91177308-0d34-0410-b5e6-96231b3b80d8