Fix memory leak

The same was done in mork driver [1] and mork driver was derived from
mozab driver.

[1] 31730671

Change-Id: I64bc85819810707511a3cebd43802066cd94a727

connectivity/source/drivers/mozab/MStatement.cxx

@@ -102,6 +102,7 @@ void OCommonStatement::disposing()
     m_pConnection = NULL;
 
     m_pSQLIterator->dispose();
+    delete m_pParseTree;
 
     dispose_ChildImpl();
     OCommonStatement_IBASE::disposing();