elf: Never set non_ir_ref_regular for debug reference

Never set non_ir_ref_regular for debug reference since references in
debug sections shouldn't impact LTO output.

	* elflink.c (elf_link_add_object_symbols): Don't check strip for
	references in debug sections when setting non_ir_ref_regular.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
diff --git a/bfd/elflink.c b/bfd/elflink.c
index 2430d60..ed0bd71 100644
--- a/bfd/elflink.c
+++ b/bfd/elflink.c
@@ -5718,9 +5718,7 @@
 	  if ((s->flags & SEC_RELOC) == 0
 	      || s->reloc_count == 0
 	      || (s->flags & SEC_EXCLUDE) != 0
-	      || ((info->strip == strip_all
-		   || info->strip == strip_debugger)
-		  && (s->flags & SEC_DEBUGGING) != 0))
+	      || (s->flags & SEC_DEBUGGING) != 0)
 	    continue;
 
 	  internal_relocs = _bfd_elf_link_info_read_relocs