vpp-swan: remove step to copy vpp_sswan source for docker image

Since vpp_sswan plugin already merged in /vpp/extras/strongswan,
no need to provide additional vpp_sswan source files for docker image.

Type: fix

Signed-off-by: Yulong Pei <yulong.pei@intel.com>
Change-Id: I35bad22b1046e0dddbcf39e1af38d589d1438239
Signed-off-by: Yulong Pei <yulong.pei@intel.com>
diff --git a/extras/strongswan/vpp_sswan/docker/configs/startup.conf b/extras/strongswan/vpp_sswan/docker/configs/startup.conf
index 5cdd389..5c1952e 100644
--- a/extras/strongswan/vpp_sswan/docker/configs/startup.conf
+++ b/extras/strongswan/vpp_sswan/docker/configs/startup.conf
@@ -2,7 +2,7 @@
         nodaemon
         full-coredump
         cli-listen /run/vpp/cli.sock
-        exec /root/vpp_sswan/docker/configs/vpp.conf
+        exec /root/vpp/extras/strongswan/vpp_sswan/docker/configs/vpp.conf
 }
 
 api-trace {