d/libxtables12.symbols: refresh file

Add new symbols.
Signed-off-by: Arturo Borrero Gonzalez <arturo@debian.org>

debian/libxtables12.symbols

@@ -16,7 +16,9 @@ libxtables.so.12 libxtables12 #MINVER#
  xtables_chain_protos@Base 1.6.0+snapshot20161117
  xtables_compatible_revision@Base 1.6.0+snapshot20161117
  xtables_find_match@Base 1.6.0+snapshot20161117
+ xtables_find_match_revision@Base 1.8.0
  xtables_find_target@Base 1.6.0+snapshot20161117
+ xtables_find_target_revision@Base 1.8.0
  xtables_free_opts@Base 1.6.0+snapshot20161117
  xtables_init@Base 1.6.0+snapshot20161117
  xtables_init_all@Base 1.6.0+snapshot20161117
@@ -57,9 +59,11 @@ libxtables.so.12 libxtables12 #MINVER#
  xtables_parse_interface@Base 1.6.0+snapshot20161117
  xtables_parse_port@Base 1.6.0+snapshot20161117
  xtables_parse_protocol@Base 1.6.0+snapshot20161117
+ xtables_parse_val_mask@Base 1.8.0
  xtables_pending_matches@Base 1.6.0+snapshot20161117
  xtables_pending_targets@Base 1.6.0+snapshot20161117
  xtables_print_num@Base 1.6.0+snapshot20161117
+ xtables_print_val_mask@Base 1.8.0
  xtables_realloc@Base 1.6.0+snapshot20161117
  xtables_register_match@Base 1.6.0+snapshot20161117
  xtables_register_matches@Base 1.6.0+snapshot20161117