zenfone6: Start using vendor_overlay

* This lets us override files in /vendor without
  relying on bind mounts ^.^

* Remove too NEED_KERNEL_MODULE_SYSTEM

Change-Id: I94c244b0329d6f6cfe7efdc77e0a3ccc22ab8843
diff --git a/device.mk b/device.mk
index 317f9a1..ccc0238 100755
--- a/device.mk
+++ b/device.mk
@@ -53,8 +53,9 @@
 
 # audio
 PRODUCT_COPY_FILES += \
-    $(LOCAL_PATH)/audio/audio_policy_configuration.xml:system/etc/audio_policy_configuration.xml \
-    $(LOCAL_PATH)/audio/audio_policy_volumes_ZS630KL.xml:system/etc/audio_policy_volumes_ZS630KL.xml
+    $(LOCAL_PATH)/audio/audio_policy_configuration.xml:$(TARGET_COPY_OUT_PRODUCT)/vendor_overlay/$(PRODUCT_TARGET_VNDK_VERSION)/etc/audio/audio_policy_configuration.xml \
+    $(LOCAL_PATH)/audio/audio_policy_configuration.xml:$(TARGET_COPY_OUT_PRODUCT)/vendor_overlay/$(PRODUCT_TARGET_VNDK_VERSION)/etc/audio_policy_configuration.xml \
+    $(LOCAL_PATH)/audio/audio_policy_volumes_ZS630KL.xml:$(TARGET_COPY_OUT_PRODUCT)/vendor_overlay/$(PRODUCT_TARGET_VNDK_VERSION)/etc/audio_policy_volumes_ZS630KL.xml
 
 # Boot control
 PRODUCT_PACKAGES += \
@@ -180,6 +181,9 @@
 PRODUCT_PACKAGES_DEBUG += \
     update_engine_client
 
+# VNDK
+PRODUCT_TARGET_VNDK_VERSION := 29
+
 # WiFi Display
 PRODUCT_PACKAGES += \
     libnl