means:
o Remove Elf64_Quarter,
o Redefine Elf64_Half to be 16-bit,
o Redefine Elf64_Word to be 32-bit,
o Add Elf64_Xword and Elf64_Sxword for 64-bit entities,
o Use Elf_Size in MI code to abstract the difference between
Elf32_Word and Elf64_Word.
o Add Elf_Ssize as the signed counterpart of Elf_Size.
MFC after: 2 weeks
relocation is not sufficient for ELF relocatable object format
modules, since accessing the module metadata involves following
pointers between different ELF sections.
This allows kldxref to correctly build linker.hints on the amd64
platform.
