nfs42: remove unused declaration

Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

fs/nfs/nfs42.h

@@ -17,7 +17,5 @@ int nfs42_proc_deallocate(struct file *, loff_t, loff_t);
 loff_t nfs42_proc_llseek(struct file *, loff_t, int);
 int nfs42_proc_layoutstats_generic(struct nfs_server *,
 				   struct nfs42_layoutstat_data *);
-/* nfs4.2xdr.h */
-extern struct rpc_procinfo nfs4_2_procedures[];
 
 #endif /* __LINUX_FS_NFS_NFS4_2_H */