Recommit "rL366894: [yaml2obj] - Allow custom fields for the SHT_UNDEF sections."
With fix: do not use `stat` tool.
Original commit message:
This is a follow-up refactoring patch for recently
introduced functionality which which reduces the code duplication
and also makes possible to redefine all possible fields of
the first SHT_NULL section (previously it was only possible to set
sh_link and sh_size).
Differential revision: https://reviews.llvm.org/D65140
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@367003 91177308-0d34-0410-b5e6-96231b3b80d8