mount_ntfs.8: Fix swapped -g user and -u group

[Josiah Frentsos]

Index: mount_ntfs.8
===================================================================
RCS file: /cvs/src/sbin/mount_ntfs/mount_ntfs.8,v
retrieving revision 1.17
diff -u -p -r1.17 mount_ntfs.8
--- mount_ntfs.8        20 Aug 2022 07:03:24 -0000      1.17
+++ mount_ntfs.8        14 Nov 2022 14:06:39 -0000
@@ -41,10 +41,10 @@
 .Sh SYNOPSIS
 .Nm mount_ntfs
 .Op Fl ai
-.Op Fl g Ar user
+.Op Fl g Ar group
 .Op Fl m Ar mask
 .Op Fl o Ar options
-.Op Fl u Ar group
+.Op Fl u Ar user
 .Ar special
 .Ar node
 .Sh DESCRIPTION