NFSv4.1: update nfs4_fattr_bitmap_maxsz

Attribute IDs assigned in RFC 5661 now require three bitmaps.
Fixes hitting a BUG_ON in xdr_shrink_bufhead when getting ACLs.
Signed-off-by: Andy Adamson <andros@netapp.com>
Cc:stable@kernel.org [2.6.39]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

fs/nfs/nfs4xdr.c

@@ -91,7 +91,7 @@ static int nfs4_stat_to_errno(int);
 #define encode_getfh_maxsz      (op_encode_hdr_maxsz)
 #define decode_getfh_maxsz      (op_decode_hdr_maxsz + 1 + \
 				((3+NFS4_FHSIZE) >> 2))
-#define nfs4_fattr_bitmap_maxsz 3
+#define nfs4_fattr_bitmap_maxsz 4
 #define encode_getattr_maxsz    (op_encode_hdr_maxsz + nfs4_fattr_bitmap_maxsz)
 #define nfs4_name_maxsz		(1 + ((3 + NFS4_MAXNAMLEN) >> 2))
 #define nfs4_path_maxsz		(1 + ((3 + NFS4_MAXPATHLEN) >> 2))