MC: Remove stream and output functions from MCObjectWriter. NFCI.

Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47043

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@332864 91177308-0d34-0410-b5e6-96231b3b80d8
5 files changed