Fix bug 34051 by handling empty .res files gracefully.

Summary:
Previously, llvm-cvtres crashes on .res files which are empty except for
the null header.  This allows the library to simply pass over them.

Subscribers: llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D37044

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@311625 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed