Update DEVSTACK_SERIES to victoria

stable/ussuri branch has been created now and
current master is for victoria.

Change-Id: I10bd20adf6ce43c6c73acaa646d425c6df6da199
diff --git a/stackrc b/stackrc
index 17641c3..c8c2738 100644
--- a/stackrc
+++ b/stackrc
@@ -255,7 +255,7 @@
 # Setting the variable to 'ALL' will activate the download for all
 # libraries.
 
-DEVSTACK_SERIES="ussuri"
+DEVSTACK_SERIES="victoria"
 
 ##############
 #