Fix for the failing gis.test

mysql-test/r/gis.result:
  result fixed
sql/item_geofunc.cc:
  new_field->init() call added

mysql-test/r/gis.result

@@ -578,7 +578,7 @@ create table t1 select GeomFromWKB(POINT(1,3));
 show create table t1;
 Table	Create Table
 t1	CREATE TABLE `t1` (
-  `GeomFromWKB(POINT(1,3))` geometry NOT NULL default ''
+  `GeomFromWKB(POINT(1,3))` geometry NOT NULL DEFAULT ''
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 drop table t1;
 CREATE TABLE `t1` (`object_id` bigint(20) unsigned NOT NULL default '0', `geo`

sql/item_geofunc.cc

@@ -27,8 +27,11 @@
 
 Field *Item_geometry_func::tmp_table_field(TABLE *t_arg)
 {
-  return new Field_geom(max_length, maybe_null, name, t_arg->s,
-                        (Field::geometry_type) get_geometry_type());
+  Field *result;
+  if ((result= new Field_geom(max_length, maybe_null, name, t_arg->s,
+                              (Field::geometry_type) get_geometry_type())))
+    result->init(t_arg);
+  return result;
 }
 
 void Item_geometry_func::fix_length_and_dec()