Update usage for the addition of -n in rev 1.35 of mv.c.

Approved by:	obrien, sheldonh (mentor).

bin/mv/mv.1

@@ -47,7 +47,7 @@
 .Op Fl v
 .Ar source target
 .Nm
-.Op  Fl f | Fl i
+.Op  Fl f | Fl i | Fl n
 .Op Fl v
 .Ar source ... directory
 .Sh DESCRIPTION

bin/mv/mv.c

@@ -380,7 +380,7 @@ usage(void)
 {
 
 	(void)fprintf(stderr, "%s\n%s\n",
-		      "usage: mv [-f | -i] [-v] source target",
-		      "       mv [-f | -i] [-v] source ... directory");
+		      "usage: mv [-f | -i | -n] [-v] source target",
+		      "       mv [-f | -i | -n] [-v] source ... directory");
 	exit(EX_USAGE);
 }