EX-3626 build: build ptlrpc_gss during ubuntu dkms

EX-3626 build: build ptlrpc_gss during ubuntu dkms

include ptlrpc_gss in dkms.conf

Lustre-change: https://review.whamcloud.com/44539

Change-Id: I952a7019b2bc5687507fdb1f274c100152dae6cd
Signed-off-by: Minh Diep <mdiep@whamcloud.com>
Reviewed-by: Sebastien Buisson <sbuisson@ddn.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/46018
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: John L. Hammond <jhammond@whamcloud.com>