message: sv2017: fix optional ports
diff: @@ -1563,11 +1563,9 @@ module_header_common:
  module_declaration:
  KW_EXTERN module_header_common ( list_of_port_declarations )? SEMI
  - | ( module_header_common (list_of_port_declarations | (LPAREN DOT MUL RPAREN) )? SEMI
  + | module_header_common (list_of_port_declarations | (LPAREN DOT MUL RPAREN) )? SEMI
  ( timeunits_declaration )? ( module_item )*
  - ) KW_ENDMODULE ( COLON identifier
  - | {_input->LA(1) != COLON}?
  - )
  + KW_ENDMODULE ( COLON identifier | {_input->LA(1) != COLON}? )
  ;
  module_keyword:
  KW_MODULE
  @@ -1755,8 +1753,8 @@ parameter_port_declaration:
  list_of_port_declarations:
  LPAREN
  (
  - ( nonansi_port ( COMMA nonansi_port )* )
  - | ( COMMA nonansi_port )+
  + ( nonansi_port ( COMMA ( nonansi_port )? )* )
  + | ( COMMA ( nonansi_port )? )+
  | ( ( attribute_instance )* ansi_port_declaration ( COMMA ( attribute_instance )* ansi_port_declaration )* )
  )? RPAREN;
  @@ -2382,8 +2380,7 @@ module_item_item:
  | specparam_declaration
  ;
  module_item:
  - nonansi_port_declaration SEMI
  - | generate_region
  + generate_region
  | ( attribute_instance )* module_item_item
  | specify_block
  | program_declaration
  