Let some more tests ignore expected output on stderr.

Let some more tests ignore expected output on stderr.
Also, use > %t instead of -o %t for output in one test since that also works
when %t already exists.

This fixes 6 testcases.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52178 91177308-0d34-0410-b5e6-96231b3b80d8