CBD-1425:  Don't make MFS_DIR or it will prevent git clone

Change-Id: Ica95ce80dc1519d2b61bf95c57056f6a75e17df5
Reviewed-on: http://review.couchbase.org/40421
Reviewed-by: Philip Labee <philip@couchbase.com>
Tested-by: Philip Labee <philip@couchbase.com>