Cleanup of sql_yacc.yy
Cleanup of sql_yacc.yy


sql/sql_yacc.yy:
  Remove useless actions from the grammar.
  Empty {} actions in the middle of a rule caused an extra reduce,
  which is affecting the parser complexity and performances.

davidl-zend/zenddbi,flynn1973/mariadb-aix,natsys/mariadb_10.2,davidl-zend/zenddbi,flynn1973/mariadb-aix,natsys/mariadb_10.2,davidl-zend/zenddbi,flynn1973/mariadb-aix,ollie314/server,davidl-zend/zenddbi,natsys/mariadb_10.2,ollie314/server,flynn1973/mariadb-aix,flynn1973/mariadb-aix,flynn1973/mariadb-aix,davidl-zend/zenddbi,natsys/mariadb_10.2,davidl-zend/zenddbi,ollie314/server,ollie314/server,natsys/mariadb_10.2,natsys/mariadb_10.2,natsys/mariadb_10.2,slanterns/server,davidl-zend/zenddbi,ollie314/server,ollie314/server,flynn1973/mariadb-aix,ollie314/server,davidl-zend/zenddbi,natsys/mariadb_10.2,flynn1973/mariadb-aix,flynn1973/mariadb-aix,davidl-zend/zenddbi,flynn1973/mariadb-aix,davidl-zend/zenddbi,ollie314/server,flynn1973/mariadb-aix,ollie314/server,natsys/mariadb_10.2,natsys/mariadb_10.2,ollie314/server,davidl-zend/zenddbi,ollie314/server,natsys/mariadb_10.2