dbwrap: fix possible memleak and false result check.

dbwrap: fix possible memleak and false result check.

A cstatus != 0 or a data.dsize != sizeof(uint32_t)
does not guarantee to have no received data referenced by data.dptr.
Therefore, make sure data.dptr is free'd.
Reusing the same data structure as data input and data output parameter
can lead to wrong results, especially when the output parameters value
is used to detect errors. Create the additional local variable outdata
to prevent this issue.

Signed-off-by: Swen Schillig <swen@linux.ibm.com>
Reviewed-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Martin Schwenke <martin@meltin.net>
Autobuild-User(master): Martin Schwenke <martins@samba.org>
Autobuild-Date(master): Thu Apr  2 11:26:32 UTC 2020 on sn-devel-184