Drop the raw_ostream required buffer size to 1.

 - As best I can tell, we have eliminated all the code which used to require a
   larger buffer size.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81912 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed