man: update examples in nilfs.8

Update the usage examples in the nilfs(8) manual page to reflect current
behavior.

The previous examples were outdated, showing timestamps from 2014 and
mount command output that differs from modern kernel behavior
(specifically regarding the "gcpid" and "relatime" mount options).

This change aligns the examples with the "What is NILFS?" section of the
official website.

[ also updated man page date to prevent inversions ]

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>

Author: konis

man/nilfs.8

@@ -1,7 +1,7 @@
 .\"  Copyright (C) 2005-2012 Nippon Telegraph and Telephone Corporation.
 .\"  Written by Ryusuke Konishi <konishi.ryusuke@gmail.com>
 .\"
-.TH NILFS 8 "Apr 2014" "nilfs-utils version 2.2"
+.TH NILFS 8 "Jan 2026" "nilfs-utils version 2.2"
 .SH NAME
 NILFS \- the new implementation of a log-structured file system
 .SH SYNOPSIS
@@ -67,23 +67,23 @@ ordinary POSIX file system.  This will invoke a cleaner process
 lists checkpoints created in the file system as follows:
 .PP
         CNO        DATE     TIME  MODE  FLG      BLKCNT       ICNT
-          1  2014-01-18 20:49:54   cp    -            4          2
-          2  2014-01-18 20:51:45   cp    -         3990         11
-          3  2014-01-18 20:51:45   cp    -         6058          3
-          4  2014-01-18 20:51:49   cp    -         4807          6
-          5  2014-01-18 20:51:49   cp    -          262          3
+          1  2024-03-16 23:49:26   cp    -            4          1
+          2  2024-03-16 23:49:44   cp    -            4          1
+          3  2024-03-16 23:50:55   cp    -         3208        625
+          4  2024-03-16 23:51:18   cp    -         2207        506
+          5  2024-03-16 23:51:23   cp    -         2204        503
         ...
 .TP
 .B chcp ss \fP2
 changes the checkpoint whose \fIcheckpoint-number\fP is two to a snapshot.
 Then the checkpoint list will become as follows:
 .PP
         CNO        DATE     TIME  MODE  FLG      BLKCNT       ICNT
-          1  2014-01-18 20:49:54   cp    -            4          2
-          2  2014-01-18 20:51:45   ss    -         3990         11
-          3  2014-01-18 20:51:45   cp    -         6058          3
-          4  2014-01-18 20:51:49   cp    -         4807          6
-          5  2014-01-18 20:51:49   cp    -          262          3
+          1  2024-03-16 23:49:26   cp    -            4          1
+          2  2024-03-16 23:49:44   ss    -            4          1
+          3  2024-03-16 23:50:55   cp    -         3208        625
+          4  2024-03-16 23:51:18   cp    -         2207        506
+          5  2024-03-16 23:51:23   cp    -         2204        503
         ...
 .TP
 .B mount \-t nilfs2 \-r \-o cp=2 \fP/dev/sdb1 /snapshot
@@ -95,8 +95,8 @@ one or more snapshots are mountable independently, so the online
 backup is possible through the snapshot mounts.
 .PP
         # mount \-t nilfs2
-        /dev/sdb1 on /nilfs type nilfs2 (rw,gcpid=13296)
-        /dev/sdb1 on /snapshot type nilfs2 (ro,cp=2)
+        /dev/sdb1 on /nilfs type nilfs2 (rw,relatime)
+        /dev/sdb1 on /snapshot type nilfs2 (ro,relatime,cp=2)
 .TP
 .B umount \fP/nilfs
 unmounts the NILFS2 file system mounted on `/nilfs' and will shut down