Bump UP4 version

Change-Id: I221980ba5ab061e89d9b1da058edd6100fd31714
diff --git a/Makefile.vars b/Makefile.vars
index 75edaee..fe254fd 100644
--- a/Makefile.vars
+++ b/Makefile.vars
@@ -30,6 +30,6 @@
 export TRELLIS_CONTROL_VERSION ?= 3.0.0
 export TRELLIS_T3_VERSION      ?= 3.0.0
 export FABRIC_TOFINO_VERSION   ?= e1cf4551b4ab74bb82a7cecf19d197698ffbc1cb
-export UP4_VERSION             ?= cac4b02ef342a0588bc3e1fcfb8d29fef1c0dfd8
+export UP4_VERSION             ?= 78071a75800a2d40751c97209f895ea938874389
 export KAFKA_ONOS_VERSION      ?= 2.4.0-SNAPSHOT
 export FABRIC_TNA_VERSION      ?= 5e47a947780d3f26a5c76644b9950892ef7ce319