Documentation: networking: Add blurb about patches in patchwork

Explain that the patch queue in patchwork should not be touched by patch
submitters.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/networking/netdev-FAQ.txt

@@ -111,6 +111,14 @@ A: Generally speaking, the patches get triaged quickly (in less than 48h).
    patch is a good way to ensure your patch is ignored or pushed to
    the bottom of the priority list.
 
+Q: I submitted multiple versions of the patch series, should I directly update
+   patchwork for the previous versions of these patch series?
+
+A: No, please don't interfere with the patch status on patchwork, leave it to
+   the maintainer to figure out what is the most recent and current version that
+   should be applied. If there is any doubt, the maintainer will reply and ask
+   what should be done.
+
 Q: How can I tell what patches are queued up for backporting to the
    various stable releases?