MDEV-29624 Fix memory leak on pushdown of derived tablebb-10.11-MDEV-29624

Deallocation of TABLE_LIST::dt_handler and TABLE_LIST::pushdown_derived
was performed in multiple places if code. This not only made the code
more difficult to maintain but also lead to memory leaks when
dt_handler and pushdown_derived were allocated but actual pushdown
of the derived table did not take place due to the whole embedding
unit pushdown.
This commit puts deallocation of TABLE_LIST::dt_handler and
TABLE_LIST::pushdown_derived to the single point - JOIN::cleanup().

1 files changed, 0 insertions, 2 deletions

diff --git a/sql/sql_select.h b/sql/sql_select.h
index 9174d5f7d93..9eb368c6088 100644
--- a/sql/sql_select.h
+++ b/sql/sql_select.h
@@ -2488,8 +2488,6 @@ public:
 
   Pushdown_derived(TABLE_LIST *tbl, derived_handler *h);
 
-  ~Pushdown_derived();
-
   int execute(); 
 };