[llvm-objcopy] Add support for nested and overlapping segments

This change adds support for nested and even overlapping segments. This means
that PT_PHDR, PT_GNU_RELRO, PT_TLS, and PT_DYNAMIC can be supported properly.

Differential Revision: https://reviews.llvm.org/D36558

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@313656 91177308-0d34-0410-b5e6-96231b3b80d8
7 files changed