The yaml reader is not specific to any file format. This patch moves
it to TargetInfo and makes validate a non virtual interface so that it
can be constructed from a single location.

The same method will be used to create a reader for llvm bitcode
files.

llvm-svn: 183740

llvm-svn: 183622

llvm-svn: 183604

Add WinLinkDriver and connect it to the existing COFF reader. Remaining
parts are still stubs, so while it can now read a COFF file, it still
cannot link or output PE/COFF files yet.

Reviewers: Bigcheese

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D865

llvm-svn: 182784