LU-7601 build: fix typo for spl/zfs added case handler

LU-7601 build: fix typo for spl/zfs added case handler

A typo has been introduced to detect SPL/ZFS DKMS versions even
when they are still in the "added" state.

Signed-off-by: Bruno Faccini <bruno.faccini@intel.com>
Change-Id: I51c269c6c35991cf1b7c26fa44769c1bc73fe20d
Reviewed-on: http://review.whamcloud.com/17829
Tested-by: Jenkins
Reviewed-by: Nathaniel Clark <nathaniel.l.clark@intel.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>