Bug#32754 - InnoDB tests do not prepare or clean up correctly

Some test cases were missing preparation to deal with failed
predecessor test cases.

Added preparation (drop table if exists) to some test cases.

mysql-test/include/innodb_rollback_on_timeout.inc

@@ -2,6 +2,10 @@
 # Bug #24200: Provide backwards compatibility mode for 4.x "rollback on
 # transaction timeout"
 #
+--disable_warnings
+drop table if exists t1;
+--enable_warnings
+
 show variables like 'innodb_rollback_on_timeout';
 create table t1 (a int unsigned not null primary key) engine = innodb;
 insert into t1 values (1);