support/init.d.examples: Do not use @PKG_PREFIX@ in service examples

I can't think of a reason to do this since these scripts are just
examples.

This is for #474.

support/init.d.examples/openvpn.in

@@ -12,10 +12,10 @@
 vpn=${RC_SVCNAME#*.}
 name="OpenVPN"
 [ "$vpn" != openvpn ] && name="$name ($vpn)"
-command=@PKG_PREFIX@/sbin/openvpn
+command=/sbin/openvpn
 
 pidfile=/var/run/"$RC_SVCNAME".pid
-: ${openvpn_dir:=@PKG_PREFIX@/etc/openvpn}
+: ${openvpn_dir:=/etc/openvpn}
 : ${openvpn_config:=$openvpn_dir/$vpn.conf}
 command_args="$openvpn_args --daemon --config $openvpn_config"
 command_args="$command_args --writepid $pidfile"