curl: fix dependencies when building with ldap/ldaps

curl: fix dependencies when building with ldap/ldaps

openldap is added as a dependency so the build will not fail,
as otherwise ldap headers are not found during configure phase

Note: due to upstream bug (now fixed) building LDAP/LDAPS support
with minimal configurations can sometimes not work, see details at:
https://github.com/curl/curl/pull/10445

Signed-off-by: Federico Pellegrin <fede@evolware.org>
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
(cherry picked from commit a999f62f5692687a5557f7a50c7c768c50f3d7d3)
Signed-off-by: Steve Sakoman <steve@sakoman.com>