* subsegs.h (struct frchain): Delete frch_seg.

	* subsegs.h (struct frchain): Delete frch_seg.
	(frchain_root): Delete.
	(seg_info): Define as macro.
	* subsegs.c (frchain_root): Delete.
	(abs_seg_info, und_seg_info, absolute_frchain): Delete.
	(subsegs_begin, subseg_change): Adjust for above.
	(subseg_set_rest): Likewise.  Add new frchain structs to seginfo
	rather than to one big list.
	(subseg_get): Don't special case abs, und sections.
	(subseg_new, subseg_force_new): Don't set frchainP here.
	(seg_info): Delete.
	(subsegs_print_statistics): Adjust frag chain control list traversal.
	* debug.c (dmp_frags):  Likewise.
	* dwarf2dbg.c (first_frag_for_seg): Don't start looking for frag
	at frchain_root.  Make use of known frchain ordering.
	(last_frag_for_seg): Likewise.
	(get_frag_fix): Likewise.  Add seg param.
	(process_entries, out_debug_aranges): Adjust get_frag_fix calls.
	* write.c (chain_frchains_together_1): Adjust for struct frchain.
	(SUB_SEGMENT_ALIGN): Likewise.
	(subsegs_finish): Adjust frchain list traversal.
	* config/tc-xtensa.c (xtensa_cleanup_align_frags): Likewise.
	(xtensa_fix_target_frags, xtensa_mark_narrow_branches): Likewise.
	(xtensa_mark_zcl_first_insns, xtensa_fix_a0_b_retw_frags): Likewise.
	(xtensa_fix_b_j_loop_end_frags): Likewise.
	(xtensa_fix_close_loop_end_frags): Likewise.
	(xtensa_fix_short_loop_frags, xtensa_sanity_check): Likewise.
	(retrieve_segment_info): Delete frch_seg initialisation.