NFS: Properly set NFS v4.2 NFSDBG_FACILITY

NFS v4.2 operations can work outside of pNFS, so dprintk() output
shouldn't be placed under NFSDBG_PNFS.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>