cleanup: cosmetic fixes

mysql-test/t/func_gconcat.test

@@ -1,9 +1,6 @@
 #
 # simple test of group_concat function
 #
---disable_warnings
-drop table if exists t1, t2;
---enable_warnings
 
 create table t1 (grp int, a bigint unsigned, c char(10) not null, d char(10) not null);
 insert into t1 values (1,1,"a","a");