error stream, in cases where the AsmParser is
being invoked by EDDisassembler. Before, they
were being sent to errs() because no error handler
was installed in the SourceMgr.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129177 91177308-0d34-0410-b5e6-96231b3b80d8