Reduce duplication of code by
* Removing from elf_common.h definitions available in os/kernel/elf.h
* Deleting elf32.h and elf64.h
* Renaming elf_common.h to elf_private.h
* Updating source to build using public and private ELF header files
together
Signed-off-by: Jessica Hamilton <jessica.l.hamilton@gmail.com>
