security/sssd2: Fix ldb and idmap library paths
The ldb library path seems incorrect as it does not work in the built-in
ldb of Samba 4.22. Fix that by using SAMBA_LDB_MODULESDIR. This should
fix the following runtime error:
```
* (2025-12-02 03:12:12): [sssd] [sysdb_ldb_connect] (0x4000): No ldb module path set in env
* (2025-12-02 03:12:12): [sssd] [sysdb_ldb_connect] (0x4000): No ldb module path set in env
* (2025-12-02 03:12:12): [sssd] [ldb] (0x0010): WARNING: Module [memberof] not found - do you need to set LDB_MODULES_PATH?
```
Also, use SAMBA_IDMAP_MODULESDIR for consistency.
PR: 291492
Approved by: portmgr blanket
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D54138
samba.mk: Add samba:self, SAMBA_LDB_MODULESDIR and SAMBA_IDMAP_MODULESDIR
The new argument, samba:self, is similar to samba:env. It allows a port
to reference samba.mk variables without adding dependencies on the Samba
port to *_DEPENDS. The difference is that samba:self is intended to be
used by Samba ports. This way we can be sure that Samba and its
consumers agree on the location of shared files and directories.
New *DIR variables are SAMBA_LDB_MODULESDIR and SAMBA_IDMAP_MODULESDIR
as required by security/sssd2.
PR: 290424
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D54136
net/samba422: Fix USES=cpe and incorporate USES=samba:self
USES=cpe has not been working as it was overwritten by another
assignment of USES later in the file. Fix that by merging those two USES
assignments into one.
Add USES=samba:self, so that we can depend on the directory paths
defined in samba.mk.
PR 290424
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D54137
