clang/test/Tooling/multi-jobs.cpp: Mark this as XFAIL:msvc for now. It has been failing since r194968.

MSVC targeted drivers (*-win32) are incapable of invoking external assembler.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@194992 91177308-0d34-0410-b5e6-96231b3b80d8