[mc-coff] Forward Linker Option flags into the .drectve section

Summary:
This is modelled on the Mach-O linker options implementation and should
support a Clang implementation of #pragma comment(lib/linker).

Reviewers: rafael

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D724

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180569 91177308-0d34-0410-b5e6-96231b3b80d8