make the test results repeatable

mysql-test/r/myisam.result

@@ -529,6 +529,7 @@ show keys from t1;
 Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment
 t1	1	a	1	a	A	NULL	NULL	NULL	YES	BTREE	disabled
 create table t2 (a int);
+set @@rand_seed1=31415926,@@rand_seed2=2718281828;
 insert t1 select * from t2;
 show keys from t1;
 Table	Non_unique	Key_name	Seq_in_index	Column_name	Collation	Cardinality	Sub_part	Packed	Null	Index_type	Comment

mysql-test/t/myisam.test

@@ -498,11 +498,12 @@ alter table t1 disable keys;
 show keys from t1;
 create table t2 (a int);
 let $i=1000;
+set @@rand_seed1=31415926,@@rand_seed2=2718281828;
 --disable_query_log
 while ($i)
 {
   dec $i;
-  eval insert t2 values (rand()*100000);
+  insert t2 values (rand()*100000);
 }
 --enable_query_log
 insert t1 select * from t2;