CBD-917: add DGM xperf config

Change-Id: Ic1c3bab574d3d5c5782819fb680fffb21b658997
Reviewed-on: http://review.couchbase.org/25593
Reviewed-by: Pavel Paulau <pavel.paulau@gmail.com>
Tested-by: Pavel Paulau <pavel.paulau@gmail.com>