dirmngr: Fix out of scope use of a var in the keyserver LDAP code.
* dirmngr/ks-engine-ldap.c (extract_attributes): Don't use a variabale out of scope and cleanup the entire pgpKeySize block.
- GnuPG-bug-id: T4229
- Signed-off-by: Werner Koch <wk@gnupg.org>