* sysdeps/powerpc/Makefile [subdir=elf]: Add new files split out of
dl-machine.h.
* sysdeps/powerpc/dl-machine.c: New file.
* sysdeps/powerpc/dl-machine.h: Move much stuff into separate
files. Revise ELF_PREFERRED_ADDRESS to take account of
the new mapping information (fixes bug involving huge bloated
web browser). Set ELF_MACHINE_PLTREL_OVERLAP.
* sysdeps/powerpc/dl-start.S: New file.
* elf/dl-load.c (_dl_map_object_from_fd): Initialise l_map_start,
l_map_end.
* elf/do-rel.h: Call elf_machine_rel only once (to save space).
* elf/dynamic-link.h: Allow PLT relocs to be in the middle of the
others. Call elf_dynamic_do_##reloc only once (to save even more
space).
* elf/link.h: Add new members l_map_start and l_map_end to keep
track of the memory map.
* elf/rtld.c (_dl_start): Initialise l_map_start for ld.so and
the executable.