[Submodule update] swss with following PR's:

abdosi · abdosi · commit 4324f307efe6 · 2020-04-19T16:38:10.000-07:00
Do not set PG to Buffer porfile mapping again if already exist. (#1261) [sub intf] Use m_lag_id to be the parent port object id when parent port is LAG (#1235)
diff --git a/src/sonic-swss b/src/sonic-swss
@@ -1 +1 @@
-Subproject commit 3f8c2fe8267d2051e098c2a71f977b70d84e84b6
+Subproject commit e9cf94aaf159c6ee30d6da7fa53fbbaa640694a8
