Adjust afs_lockctl to compensate for byte-range lock fixes

Adjust afs_lockctl to compensate for byte-range lock fixes

As of commit 49b7bbdd3b45df694fadbef48f9ed99d9bfe07b9, l_len is no
longer 1 less than it should be.  Update afs_lockctl to expect this.

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Change-Id: I3fb7665457d489e56564b14933795084a0958d6f
Reviewed-on: http://gerrit.openafs.org/1353
Reviewed-by: Simon Wilkinson <sxw@inf.ed.ac.uk>
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Tested-by: Derrick Brashear <shadow@dementia.org>
(cherry picked from commit 99e704c791bbedd9aa3fc1a0feb9493b0eaefd7d)
Reviewed-on: http://gerrit.openafs.org/1373
(cherry picked from commit 89193695da6dc8946e4a03ed40081a91050ca5dc)