zenfone8: Enable virtual a/b ota

Change-Id: Iefa2ddb55a8155819f3f1599ce195829e9c37de4
diff --git a/device.mk b/device.mk
index 52359b1..3df8eb5 100755
--- a/device.mk
+++ b/device.mk
@@ -31,6 +31,7 @@
 
 # A/B
 ENABLE_VIRTUAL_AB := true
+$(call inherit-product, $(SRC_TARGET_DIR)/product/virtual_ab_ota.mk)
 
 AB_OTA_POSTINSTALL_CONFIG += \
     RUN_POSTINSTALL_system=true \