[llvm-objdump] Further rearrange llvm-objdump sections for compatability

Summary:
rL371826 rearranged some output from llvm-objdump for GNU objdump compatability, but there still seem to be some more.

I think this rearrangement is a little closer. Overview of the ordering which matches GNU objdump:
* Archive headers
* File headers
* Section headers
* Symbol table
* Dwarf debugging
* Relocations (if `--disassemble` is not used)
* Section contents
* Disassembly

Reviewers: jhenderson, justice_adams, grimar, ychen, espindola

Reviewed By: jhenderson

Subscribers: aprantl, emaste, arichardson, jrtc27, atanasyan, seiya, llvm-commits, MaskRay

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68066

llvm-svn: 373671