Don't call bfd_link_hash_table_free

Don't call bfd_link_hash_table_free

Freeing the linker hash table is a royal pain.  It can't be freed
before the _bfd_write_contents call in bfd_close, because some target
bfd_write_contents functions access the hash table.  It can't be freed
after bfd_close either, since bfd_alloc memory holding side data
structures disappears (PR17047).  Clearly the only place it can be freed
is actually in bfd_close.  This patch doesn't do that, but kills off
the existing means of freeing the hash table via a bfd target xvec call.

bfd/
	PR 17047
	* targets.c (BFD_JUMP_TABLE): Delete NAME##_bfd_link_hash_table_free.
	(struct bfd_target <_bfd_link_hash_table_free>): Delete.
	* bfd.c (bfd_link_hash_table_free): Don't define.
	* aout-adobe.c, * aout-target.h, * aout-tic30.c, * binary.c, * bout.c,
	* coff64-rs6000.c, * coffcode.h, * elf-m10300.c, * elf32-arm.c,
	* elf32-avr.c, * elf32-hppa.c, * elf32-i386.c, * elf32-m68hc11.c,
	* elf32-m68hc12.c, * elf32-m68k.c, * elf32-metag.c, * elf32-nios2.c,
	* elf32-sparc.c, * elf32-xgate.c, * elf64-ia64-vms.c, * elf64-ppc.c,
	* elf64-sparc.c, * elf64-x86-64.c, * elfnn-aarch64.c, * elfnn-ia64.c,
	* elfxx-target.h, * i386msdos.c, * i386os9k.c, * ieee.c, * ihex.c,
	* libbfd-in.h, * libecoff.h, * mach-o-target.c, * mmo.c,
	* nlm-target.h, * oasys.c, * pef.c, * plugin.c, * ppcboot.c, * som.c,
	* srec.c, * tekhex.c, * verilog.c, * versados.c, * vms-alpha.c,
	* xsym.c: Don't define various link_hash_table_free defines, and
	remove from bfd_target vars.  Temporarily reference some of the
	target link_hash_table_free functions to avoid warnings.
	* bfd-in2.h: Regenerate.
	* libbfd.h: Regenerate.
ld/
	PR 17047
	* ldlang.c (output_bfd_hash_table_free_fn): Delete.
	(open_output): Don't set it..
	* ldmain.c (ld_cleanup): ..or call it.