nfsv41: use sort timeout between door and pool manager

NFS client will backoff if it will notice that server is
not responsive. Use short timeouts to keep the pipe full.

Acked-by: Gerd Behrmann
Target: master
Require-book: no
Require-notes: no
(cherry picked from commit a6ec39adcfe0497b9e71feba37956e4b3142d932)
Signed-off-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Merge pull request #345 from kofemann/short-nfs-timeout-2.6

nfsv41: use sort timeout between door and pool manager