dirmngr:w32: Fix ldap_* types
* dirmngr/ks-engine-ldap.c: when compiling with Windows/MinGW headers, `ldap_parse_page_control` and `ldap_parse_result` expects `ULONG`. This has become a hard error when using GCC 15.
- Signed-off-by: Zhang Maiyun <me@maiyun.me>