USE_CPP_CONN is unused

...ever since 4946c62f29 "mysqlconnector: initial
import from CWS mysqlnative"

Change-Id: I787d2ac5e48be307f47e41ecac907c36b07a92ea

mysqlc/source/mysqlc_statement.cxx

@@ -35,8 +35,6 @@
 #include <osl/diagnose.h>
 #include <osl/thread.h>
 
-#define USE_CPP_CONN 1
-
 using namespace connectivity::mysqlc;
 //------------------------------------------------------------------------------
 using namespace com::sun::star::uno;