Enable assistant on all devices

Change-Id: I7877a389146ca8fd3f1aaa97a4348fc24470884e
diff --git a/config/common.mk b/config/common.mk
index 26873b6..3ddcd72 100644
--- a/config/common.mk
+++ b/config/common.mk
@@ -8,7 +8,8 @@
     ro.com.android.wifi-watchlist=GoogleGuest \
     ro.setupwizard.enterprise_mode=1 \
     ro.com.android.dateformat=MM-dd-yyyy \
-    ro.com.android.dataroaming=false
+    ro.com.android.dataroaming=false \
+    ro.opa.eligible_device=true
 
 PRODUCT_PROPERTY_OVERRIDES += \
     ro.build.selinux=1