alpha and s390x gratuitously use 64-bit entries (wasting 2x space and
cache utilization) despite the values always being 32-bit.
based on patch by Bobby Bingham, with changes suggested by Alexander
Monakov to use the public Elf_Symndx type from link.h (and make it
properly variable by arch) rather than adding new internal
infrastructure for handling the type.
Rich Felker