Bump UP4 version again

Change-Id: I39025b48dbcd1e9b662a6603d231c0bb077fd291
diff --git a/Makefile.vars b/Makefile.vars
index fe254fd..1964c47 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             ?= 78071a75800a2d40751c97209f895ea938874389
+export UP4_VERSION             ?= 74b8c5fad3315dd7d48f299abbd044b010638c13
 export KAFKA_ONOS_VERSION      ?= 2.4.0-SNAPSHOT
 export FABRIC_TNA_VERSION      ?= 5e47a947780d3f26a5c76644b9950892ef7ce319