* config/xtensa-istack.h (TInsn): Remove record_fix and sub_symbol

	* config/xtensa-istack.h (TInsn): Remove record_fix and sub_symbol
	fields.
	* config/tc-xtensa.h (xtensa_frag_type): Remove slot_sub_symbols field.
	* config/tc-xtensa.c (md_apply_fix): Check for unexpected uses of
	subtracted symbols.
	(relaxation_requirements): Add pfinish_frag argument and use it to
	replace setting tinsn->record_fix fields.
	(xg_assemble_vliw_tokens): Adjust calls to relaxation_requirements
	and vinsn_to_insnbuf.  Remove references to record_fix and
	slot_sub_symbols fields.
	(xtensa_mark_narrow_branches): Delete unused code.
	(is_narrow_branch_guaranteed_in_range): Handle expr that is not just
	a symbol.
	(convert_frag_immed): Adjust vinsn_to_insnbuf call and do not set
	record_fix fields.
	(tinsn_immed_from_frag): Remove code for handling slot_sub_symbols.
	(vinsn_to_insnbuf): Change use of record_fixup argument, replacing use
	of the record_fix field.  Simplify error messages for unexpected
	symbolic operands.
	(set_expr_symbol_offset_diff): Delete.