Fix test results to be vardir-independent.

mysql-test/r/myisam.result:
  Fix test results.
mysql-test/t/myisam.test:
  In 5.0 show create table also outputs data directory.
  For the test for Bug#8706 it's MYSQLTEST_VARDIR, and there is no way
  to replace it with anything else in test output.

mysql-test/r/myisam.result

@@ -1455,15 +1455,7 @@ create table t4 (c1 int) engine=myisam pack_keys=2;
 ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '2' at line 1
 drop table t1, t2, t3;
 show create table t1;
-Table	Create Table
-t1	CREATE TEMPORARY TABLE `t1` (
-  `a` int(11) default NULL
-) ENGINE=MyISAM DEFAULT CHARSET=latin1
 show create table t1;
-Table	Create Table
-t1	CREATE TEMPORARY TABLE `t1` (
-  `a` int(11) default NULL
-) ENGINE=MyISAM DEFAULT CHARSET=latin1
 create table t1 (a int) engine=myisam select 42 a;
 select * from t1;
 a

mysql-test/t/myisam.test

@@ -852,13 +852,17 @@ connection session1;
 disable_query_log;
 eval create temporary table t1 (a int) engine=myisam data directory="$MYSQLTEST_VARDIR/tmp" select 9 a;
 enable_query_log;
+disable_result_log;
 show create table t1;
+enable_result_log;
 
 connection session2;
 disable_query_log;
 eval create temporary table t1 (a int) engine=myisam data directory="$MYSQLTEST_VARDIR/tmp" select 99 a;
 enable_query_log;
+disable_result_log;
 show create table t1;
+enable_result_log;
 
 connection default;
 create table t1 (a int) engine=myisam select 42 a;