man: update openrc-shutdown man page

Add the new wtmp options and fix some cross references.

man/openrc-shutdown.8

@@ -16,25 +16,33 @@
 .Nd bring the system down
 .Sh SYNOPSIS
 .Nm
+.Op Fl d , -no-write
+.Op Fl D , -dry-run
 .Op Fl H , -halt
 .Op Fl k , -kexec
 .Op Fl p , -poweroff
 .Op Fl R , -reexec
 .Op Fl r , -reboot
+.Op Fl s , -single
+.Op Fl w , -write-only
 .Sh DESCRIPTION
 .Nm
-is the utility that communicates with openrc-init(8) to bring down the
-system or instruct openrc-init to re-execute itself. It supports the
-following options:
+is the utility that communicates with
+.Xr openrc-init 8
+to bring down the system or instruct openrc-init to re-execute itself.
+It supports the following options:
 .Bl -tag -width "poweroff"
-.It Fl d , -dry-run
+.It Fl d , -no-write
+Do not write the wtmp boot record.
+.It Fl D , -dry-run
 Print the action that would be taken without executing it. This is to
 allow testing.
 .It Fl H , -halt
 Stop all services, kill all remaining processes and halt the system.
 .It Fl k , -kexec
 Stop all services, kill all processes and boot directly into a new
-kernel loaded via kexec(8).
+kernel loaded via
+.Xr kexec 8 .
 .It Fl p , -poweroff
 Stop all services, kill all processes and power off the system.
 .It Fl R , -reexec
@@ -42,10 +50,11 @@ instruct openrc-init to re-exec itself. This should be used after an
 upgrade of OpenRC if you are using openrc-init as your init process.
 .It Fl r , -reboot
 Stop all services, kill all processes and reboot the system.
+.It Fl s , -single
+Stop all services, kill all processes and move to single user mode.
+.It Fl w , -write-only
+Stop all services, kill all processes and move to single user mode.
 .El
-.Pp
-If none of these options are given, the default is to move the system
-into single user mode.
 .Sh SEE ALSO
 .Xr openrc-init 8 ,
 .Xr kexec 8 ,