NFS: nfs_show_stats; for_each_possible_cpu(), not NR_CPUS

Convert a for-loop that explicitly references "NR_CPUS" into the
potentially more efficient for_each_possible_cpu() construct.
Signed-off-by: John Hawkes <hawkes@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

fs/nfs/inode.c

@@ -700,12 +700,9 @@ static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
 	/*
 	 * Display superblock I/O counters
 	 */
-	for (cpu = 0; cpu < NR_CPUS; cpu++) {
+	for_each_possible_cpu(cpu) {
 		struct nfs_iostats *stats;
 
-		if (!cpu_possible(cpu))
-			continue;
-
 		preempt_disable();
 		stats = per_cpu_ptr(nfss->io_stats, cpu);