c++/modules: stream TREE_UNAVAILABLE and LAMBDA_EXPR_REGEN_INFO

Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for
trunk?

-- >8 --

gcc/cp/ChangeLog:

	* module.cc (trees_out::core_bools): Stream TREE_UNAVAILABLE.
	(trees_in::core_bools): Likewise.
	(trees_out::core_vals): Stream LAMBDA_EXPR_REGEN_INFO.
	(trees_in::core_vals): Likewise.

gcc/cp/module.cc

@@ -5353,6 +5353,7 @@ trees_out::core_bools (tree t)
       WB (t->base.u.bits.user_align);
       WB (t->base.u.bits.nameless_flag);
       WB (t->base.u.bits.atomic_flag);
+      WB (t->base.u.bits.unavailable_flag);
       break;
     }
 
@@ -5533,6 +5534,7 @@ trees_in::core_bools (tree t)
       RB (t->base.u.bits.user_align);
       RB (t->base.u.bits.nameless_flag);
       RB (t->base.u.bits.atomic_flag);
+      RB (t->base.u.bits.unavailable_flag);
       break;
     }
 
@@ -6319,6 +6321,7 @@ trees_out::core_vals (tree t)
       WT (((lang_tree_node *)t)->lambda_expression.capture_list);
       WT (((lang_tree_node *)t)->lambda_expression.this_capture);
       WT (((lang_tree_node *)t)->lambda_expression.extra_scope);
+      WT (((lang_tree_node *)t)->lambda_expression.regen_info);
       /* pending_proxies is a parse-time thing.  */
       gcc_assert (!((lang_tree_node *)t)->lambda_expression.pending_proxies);
       if (state)
@@ -6815,6 +6818,7 @@ trees_in::core_vals (tree t)
       RT (((lang_tree_node *)t)->lambda_expression.capture_list);
       RT (((lang_tree_node *)t)->lambda_expression.this_capture);
       RT (((lang_tree_node *)t)->lambda_expression.extra_scope);
+      RT (((lang_tree_node *)t)->lambda_expression.regen_info);
       /* lambda_expression.pending_proxies is NULL  */
       ((lang_tree_node *)t)->lambda_expression.locus
 	= state->read_location (*this);