Build product/odm build.prop with Soong

Bug: 322090587
Test: compare build.prop before and after, boot
Change-Id: I7a7dc785030a0c17e5c09b7f65c978fe9bbcb7a7
diff --git a/android/config.go b/android/config.go
index 3b30af8..d13e5ab 100644
--- a/android/config.go
+++ b/android/config.go
@@ -2046,6 +2046,10 @@
 	return PathsForSource(ctx, c.productVariables.SystemExtPropFiles)
 }
 
+func (c *config) ProductPropFiles(ctx PathContext) Paths {
+	return PathsForSource(ctx, c.productVariables.ProductPropFiles)
+}
+
 func (c *config) EnableUffdGc() string {
 	return String(c.productVariables.EnableUffdGc)
 }