PR 11108

	PR 11108
	* symtab.h (class Symbol): Remove fields is_target_special_ and
	has_plt_offset_.  Add field is_defined_in_discarded_section_.
	(Symbol::is_defined_in_discarded_section): New function.
	(Symbol::set_is_defined_in_discarded_section): New function.
	(Symbol::has_plt_offset): Rewrite.
	(Symbol::set_plt_offset): Verify that new offset is not -1U.
	* symtab.cc (Symbol::init_fields): Initialize plt_offset_ to -1U.
	Don't initialize is_target_special_ or has_plt_offset_.
	Initialize is_defined_in_discarded_section_.
	(Symbol_table::add_from_relobj): If appropriate, set
	is_defined_in_discarded_section.
	* resolve.cc (Symbol::override_base_with_special): Don't test
	is_target_special_.  Change has_plt_offset_ to has_plt_offset().
	* target-reloc.h (relocate_section): Do special handling for
	symbols defined in discarded sections for global symbols as well
	as local symbols.