[yaml2obj] Make e_phoff and e_phentsize 0 if there are no program headers
Summary: It says [[ http://www.sco.com/developers/gabi/latest/ch4.eheader.html | here ]] that if there are no program headers than e_phoff should be 0, but currently it is always set after the header. GNU's `readelf` (but not `llvm-readelf`) complains about this: `readelf: Warning: possibly corrupt ELF header - it has a non-zero program header offset, but no program headers`.
Reviewers: jhenderson, grimar, MaskRay, rupprecht
Reviewed By: jhenderson, grimar, MaskRay
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D67054
llvm-svn: 371162