Since UNLOCK TABLES will commit the transaction (and thus release
all InnoDB locks held by it), it is unnecessary to release the
user-requested table locks separately.


innobase/include/lock0lock.h:
  Remove references to LOCK_TABLE_EXP and LOCK_TABLE_TRANSACTIONAL.
  Remove lock_release_tables_off_kernel().
innobase/include/row0mysql.h:
  Remove row_unlock_tables_for_mysql().
innobase/include/trx0trx.h:
  Remove n_lock_table_exp and n_lock_table_transactional.
innobase/lock/lock0lock.c:
  Remove references to LOCK_TABLE_EXP and LOCK_TABLE_TRANSACTIONAL.
  Remove lock_release_tables_off_kernel().
  Remove references to trx->n_lock_table_exp
  and trx->n_lock_table_transactional.
innobase/row/row0mysql.c:
  Remove row_unlock_tables_for_mysql().
  Remove references to LOCK_TABLE_TRANSACTIONAL and LOCK_TABLE_EXP.
innobase/trx/trx0trx.c:
  Remove n_lock_table_exp and n_lock_table_transactional.
sql/ha_innodb.cc:
  Remove references to LOCK_TABLE_EXP and LOCK_TABLE_TRANSACTIONAL
  and row_unlock_tables_for_mysql().