openntpd: fix help text

Help text should be indented with <tab><space><space> and contain a link
to the upstream website.

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

package/openntpd/Config.in

@@ -1,7 +1,9 @@
 config BR2_PACKAGE_OPENNTPD
 	bool "openntpd"
 	help
-	     OpenNTPD is an easy to use implementation of the Network Time
-	     Protocol. It provides the ability to sync the local clock
-	     to remote NTP servers and can act as NTP server itself,
-	     redistributing the local clock. It just works.
+	  OpenNTPD is an easy to use implementation of the Network Time
+	  Protocol. It provides the ability to sync the local clock
+	  to remote NTP servers and can act as NTP server itself,
+	  redistributing the local clock. It just works.
+
+	  http://www.openntpd.org/