lockd: Remove unnecessary BUG_ON()s in the xdr client code

- Offset bound checks are done in the NFS client code.
- So are filehandle size checks
- The cookie length is a constant
- The utsname()->nodename is already bounded

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

diff --cc fs/lockd/clnt4xdr.c
Simple merge

diff --cc fs/lockd/clntxdr.c
Simple merge