PR ld/12365

	PR ld/12365
	PR ld/12696
include/
	* bfdlink.h (ENUM_BITFIELD): Define.
	(struct bfd_link_hash_entry): Make "type" a bitfield.  Add "non_ir_ref".
	(struct bfd_link_callbacks <notice>): Pass bfd_link_hash_entry pointer
	rather than "name".
bfd/
	* coff-aux.c (coff_m68k_aux_link_add_one_symbol): Update "notice" call.
	* linker.c (_bfd_link_hash_newfunc): Clear bitfields.
	(_bfd_generic_link_add_one_symbol): Update "notice" call.
	* elflink.c (_bfd_elf_merge_symbol): Don't skip weak redefs when
	it is a redef of an IR symbol in a real BFD.
ld/
	* ldmain.c (notice): Delete "name" param, add "h".
	* plugin.c (plugin_notice): Likewise.  Set non_ir_ref.  Handle
	redefinitions of IR symbols in real BFDs.
	(plugin_multiple_definition, plugin_multiple_common): Delete.
	(non_ironly_hash, init_non_ironly_hash): Delete.
	(is_visible_from_outside): Traverse entry_symbol chain.
	(get_symbols): Use non_ir_ref flag rather than hash lookup.