Updated git submodules

Project: netvirt master a4793f9d20883403af79765b9d59dfa1062fe121

BUG 8969 - Fix Exeption when clearing external router GW

When clearing the router GW, the flow entry for router GW
on the NAPT primary switch is also removed.
Exception occurs when we try to delete the router GW
but there is no NAPT primary switch.

Fix: check for existence of NAPT primary switch
before deleting the router GW flow on the switch.
Also downgrade ERROR to DEBUG log level when primary
NAPT switch can not be found since this could
happen when no internal network attaches to the router yet.

Change-Id: I7ebc0d60183954044aeb8a4e8f062b4d227f6c76
Signed-off-by: Vinh Nguyen <vinh.nguyen@hcl.com>

diff --git a/docs/submodules/netvirt b/docs/submodules/netvirt
index a48e9f1da21e75bedeb62214534b9c77c8efb43c..a4793f9d20883403af79765b9d59dfa1062fe121 160000 (submodule)
--- a/docs/submodules/netvirt
+++ b/docs/submodules/netvirt
@@ -1 +1 @@
-Subproject commit a48e9f1da21e75bedeb62214534b9c77c8efb43c
+Subproject commit a4793f9d20883403af79765b9d59dfa1062fe121