[profile] Disable instrprof-get-filename-merge-mode.c on Windows

The Windows bots are failing with:

clang: warning: argument unused during compilation: '-dynamiclib' [-Wunused-command-line-argument]

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@375315 91177308-0d34-0410-b5e6-96231b3b80d8