Remove the linker's reliance on BSD cruft and use the glibc-style
ElfW macro. (Other code too, but the linker contains the majority
of the code that needs to work for Elf32 and Elf64.)
All platforms need dl_iterate_phdr_static, so it doesn't make sense
to have that part of the per-architecture configuration.
Bug: 12476126
Change-Id: I1d7f918f1303a392794a6cd8b3512ff56bd6e487
include/elf.h contains basically the same values as
linux/auxvec.h. Eliminate dups.
include/sys/exec_elf.h contains basically the same
values as linux/elf.h. Eliminate dups.
Change-Id: I66b8358161bb52223bb657f8f73ba28b324f4fa3