CBD-1425:  make clean steps run from TLM_DIR

Change-Id: I3fd1a8782eab6b2b2d86085a3df4f16a1059e948
Reviewed-on: http://review.couchbase.org/40426
Reviewed-by: Philip Labee <philip@couchbase.com>
Tested-by: Philip Labee <philip@couchbase.com>