flag: fix the comments

Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>

pkg/mflag/flag.go

@@ -23,12 +23,12 @@
 		flag.Var(&flagVal, []string{"name"}, "help message for flagname")
 	For such flags, the default value is just the initial value of the variable.
 
-	You can also add "deprecated" flags, they are still usable, bur are not shown
+	You can also add "deprecated" flags, they are still usable, but are not shown
 	in the usage and will display a warning when you try to use them:
-		var ip = flag.Int([]string{"f", "#flagname", "-flagname"}, 1234, "help message for flagname")
-	this will display: `Warning: '-flagname' is deprecated, it will be replaced by '--flagname' soon. See usage.` and
+		var ip = flag.Int([]string{"#f", "#flagname", "-flagname2"}, 1234, "help message for flagname")
+	this will display: `Warning: '--flagname' is deprecated, it will be replaced by '--flagname2' soon. See usage.` and
 		var ip = flag.Int([]string{"f", "#flagname"}, 1234, "help message for flagname")
-	will display: `Warning: '-t' is deprecated, it will be removed soon. See usage.`
+	will display: `Warning: '-f' is deprecated, it will be removed soon. See usage.`
 
 	You can also group one letter flags, bif you declare
 		var v = flag.Bool([]string{"v", "-verbose"}, false, "help message for verbose")