* libelf.h: Rename to elf-bfd.h to avoid conflict with

	* libelf.h:  Rename to elf-bfd.h to avoid conflict with
	systems that have a system <libelf.h>.
	* Makefile.in: Globally replace libelf.h with elf-bfd.h.
	* bfd.c, elf.c, elf32-arc.c, elf32-gen.c, elf32-hppa.c,
	elf32-hppa.h, elf32-i386.c, elf32-i860.c, elf32-m68k.c,
	elf32-m88k.c, elf32-mips.c, elf32-ppc.c, elf32-sparc.c,
	elf64-gen.c, elf64-sparc.c, elfcode.h, elflink.c,
	elfxx-target.h: Include elf-bfd.h rather than libelf.h.
	* elfxx-target.h: Change libelf.h reference to elf-bfd.h.