- revert previous changes from configure.ac script in order to re-use
the existing logic, as well as the gitlab ci flag which check build
with two combinations.
- Conditionally build LMDB source code based on HAVE_LMDB. So if
--without-lmdb is used, HAVE_LMDB won't be set and LMDB source code
will be compiled and included in libisc. This enable code using LMDB
to link no matter LMDB is OS-provided or not.
- Regarding the LMDB headers, and in order to make future LMDB update
easier, all original OpenLDAP code is wrapped under
lib/isc/openldap-lmdb including the headers. This avoid extra
changes (putting aside liscence header) to mdb.c to find out its
headers. The counter-part is the relative inclusion of this header
from isc/lmdb.h header, but it's probably a good idea to not make
this header public anyway.
- update LMDB license to add BIND9 SPDX headers but mentioning LMDB
lisence