commit 48385408 upstream.

27b11428 ("nfsd4: remove lockowner when removing lock stateid")
introduced a memory leak.
Reported-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>