Use regular module to build wpa_supplicant.conf

Now PRODUCT_COPY_FILES is not allowed in module makefiles.
Bug: 3003508

Change-Id: I55d641c470858de87097f1af3531df0e8e3ca5b1
diff --git a/wpa_supplicant_conf.mk b/wpa_supplicant_conf.mk
index 7033487..c7aa279 100644
--- a/wpa_supplicant_conf.mk
+++ b/wpa_supplicant_conf.mk
@@ -22,16 +22,23 @@
 
 ########################
 
-WPA_SUPPLICANT_CONF_GENERATED := $(call intermediates-dir-for,ETC,wpa_supplicant.conf)/wpa_supplicant.conf
+LOCAL_MODULE := wpa_supplicant.conf
+LOCAL_MODULE_CLASS := ETC
+LOCAL_MODULE_TAGS := optional
+LOCAL_MODULE_PATH := $(TARGET_OUT_ETC)/wifi
+
+include $(BUILD_SYSTEM)/base_rules.mk
+
 WPA_SUPPLICANT_CONF_TEMPLATE := $(LOCAL_PATH)/wpa_supplicant.conf
 WPA_SUPPLICANT_CONF_SCRIPT := $(LOCAL_PATH)/wpa_supplicant_conf.sh
-$(WPA_SUPPLICANT_CONF_GENERATED): $(WPA_SUPPLICANT_CONF_TEMPLATE) $(WPA_SUPPLICANT_CONF_SCRIPT)
+$(LOCAL_BUILT_MODULE): PRIVATE_WIFI_DRIVER_SOCKET_IFACE := $(WIFI_DRIVER_SOCKET_IFACE)
+$(LOCAL_BUILT_MODULE): PRIVATE_WPA_SUPPLICANT_CONF_TEMPLATE := $(WPA_SUPPLICANT_CONF_TEMPLATE)
+$(LOCAL_BUILT_MODULE): PRIVATE_WPA_SUPPLICANT_CONF_SCRIPT := $(WPA_SUPPLICANT_CONF_SCRIPT)
+$(LOCAL_BUILT_MODULE) : $(WPA_SUPPLICANT_CONF_TEMPLATE) $(WPA_SUPPLICANT_CONF_SCRIPT)
 	@echo Target wpa_supplicant.conf: $@
 	@mkdir -p $(dir $@)
-	$(hide) WIFI_DRIVER_SOCKET_IFACE="$(WIFI_DRIVER_SOCKET_IFACE)" \
-		bash $(WPA_SUPPLICANT_CONF_SCRIPT) $(WPA_SUPPLICANT_CONF_TEMPLATE) > $@
-
-PRODUCT_COPY_FILES += $(WPA_SUPPLICANT_CONF_GENERATED):system/etc/wifi/wpa_supplicant.conf
+	$(hide) WIFI_DRIVER_SOCKET_IFACE="$(PRIVATE_WIFI_DRIVER_SOCKET_IFACE)" \
+		bash $(PRIVATE_WPA_SUPPLICANT_CONF_SCRIPT) $(PRIVATE_WPA_SUPPLICANT_CONF_TEMPLATE) > $@
 
 ########################