Build product/odm build.prop with Soong

Bug: 322090587
Test: compare build.prop before and after, boot
Change-Id: Iab157cf313d62c1c95ef66dd0a2b9563ee60ab46
diff --git a/core/config.mk b/core/config.mk
index bd905dc..2f18add 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -1254,7 +1254,11 @@
 TARGET_SYSTEM_EXT_PROP := $(wildcard $(TARGET_DEVICE_DIR)/system_ext.prop)
 endif
 
-.KATI_READONLY += TARGET_SYSTEM_PROP TARGET_SYSTEM_EXT_PROP
+ifeq ($(TARGET_PRODUCT_PROP),)
+TARGET_PRODUCT_PROP := $(wildcard $(TARGET_DEVICE_DIR)/product.prop)
+endif
+
+.KATI_READONLY := TARGET_SYSTEM_PROP TARGET_SYSTEM_EXT_PROP TARGET_PRODUCT_PROP
 
 include $(BUILD_SYSTEM)/sysprop_config.mk