Forward-port: Fix wrong filename in ganeti-watcher manpage

Reviewed-by: iustinp

man/ganeti-watcher.sgml

@@ -68,7 +68,7 @@
 
     <para>
       The command has a state file located at
-      <filename>@LOCALSTATEDIR@/lib/ganeti/restart_state</filename> and a log
+      <filename>@LOCALSTATEDIR@/lib/ganeti/watcher.data</filename> and a log
       file at
       <filename>@LOCALSTATEDIR@/log/ganeti/watcher.log</filename>. Removal of
       either file will not affect correct operation; the removal of