Use RRO for product-specific resources

Currently TeleService is compiled and linked with the argument
'--product {PRODUCT_CHARACTERISTICS}' to select product-specific
resources. But that causes the app to depend on the product
characteristics, making differences of system.img among targets.

Setting generate_product_characteristics_rro will automatically
generate an RRO package which contains resources having
product="{PRODUCT_CHARACTERISTICS}"'. The RRO package will be
installed to /product partition. TeleService will be compiled with
'--product default', making system.img identical to all targets.

Bug: 322932641
Test: TH
Change-Id: Ida005dd8ae58e65f2c3ee5917ae992681c5efd35
diff --git a/Android.bp b/Android.bp
index 1e7b954..b51af0b 100644
--- a/Android.bp
+++ b/Android.bp
@@ -79,6 +79,8 @@
     proto: {
         type: "lite",
     },
+
+    generate_product_characteristics_rro: true,
 }
 
 // Allow other applications to use public constants from SlicePurchaseController