fix sporadic failures of rpl.rpl_drop_temp test

the test forces create_tmp_table_binlog_formats="statement,mixed",
so CREATE TEMPORARY TABLE is always logged, and the test should
thus always wait for it

Author: vuvova

mysql-test/suite/rpl/t/rpl_drop_temp.test

@@ -85,11 +85,8 @@ SET SESSION binlog_format=ROW;
 --disconnect con1
 
 -- connection master
-if (`SELECT FIND_IN_SET(@@BINLOG_FORMAT,@@CREATE_TMP_TABLE_BINLOG_FORMATS) > 0`)
-{
 --let $wait_binlog_event= DROP
 --source include/wait_for_binlog_event.inc
-}
 --sync_slave_with_master
 SHOW STATUS LIKE 'Slave_open_temp_tables';