Package samba-util-private-headers: Information

- Fix backward compatibility to fixed version of libldb with CVE-2021-20254.
- Replace auth and vfs libraries from samba-libs to samba-dc-libs and samba packages.
- Build without separated libnetapi private library.

- Fix buffer overrun in sids_to_unixids() (Fixes: CVE-2021-20254)
- Final migration to /run directory (Closes: 35891, 36652, 39992)
- Avoid build problems on e2k

- Multiple build fixes:
  + Revert to use macros for e2k (due ALT#36315 was fixed).
  + Add samba-common-client subpackage with smb.conf and its staff only.
  + Add dumpmscat utility with libtasn1-devel and libtasn1-utils buildrequires.
  + Replace mdfind and mvxattr to samba-client from samba-common-tools.
  + Support pdbedit in separate heimdal server build.
  + Add /usr/include/samba-4.0 directory to devel packages.
  + Shift shared libraries between samba-libs and samba-common-libs to avoid
    cyclical dependencies.