NFS: Add optional post-op getattr instruction to the NFSv4 file close.

"Optional" means that the close call will not fail if the getattr
 at the end of the compound fails.
 If it does succeed, try to refresh inode attributes.

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

include/linux/nfs_xdr.h

@@ -153,10 +153,13 @@ struct nfs_closeargs {
 	nfs4_stateid *		stateid;
 	struct nfs_seqid *	seqid;
 	int			open_flags;
+	const u32 *		bitmask;
 };
 
 struct nfs_closeres {
 	nfs4_stateid            stateid;
+	struct nfs_fattr *	fattr;
+	const struct nfs_server *server;
 };
 /*
  *  * Arguments to the lock,lockt, and locku call.