LU-7228 build: make lustre rpm also provide lustre-client

LU-7228 build: make lustre rpm also provide lustre-client

An application packaged in an rpm has to depend on either lustre or
lustre-client. Since the lustre rpm also includes everything the
lustre-client does, it should also provides lustre-client.

That way an application rpm only has to require lustre-client and not
juggle between a lustre or lustre-client dependency.

Signed-off-by: frank zago <fzago@cray.com>
Change-Id: I46ae8a96b0fbc6153a288bf45896f7b4ed1dfddc
Reviewed-on: http://review.whamcloud.com/16673
Tested-by: Jenkins
Reviewed-by: Dmitry Eremin <dmitry.eremin@intel.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Thomas LEIBOVICI <thomas.leibovici@cea.fr>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>