Pass archive files to link.exe if they contain at least one native object file.

Some archive files created during chromium build contains both BC
and native files. If that's the case, we want to pass the archive
file to link.exe. Otherwise, the MSVC linker would complain that
there's an unresolved symbol in a given set of files.

I cannot explain why link.exe doesn't complain about the presence
of bitcode files in this case, but it seems link.exe doesn't touch BC.

llvm-svn: 297229