ExactCalculator: Move to /product

Change-Id: I9b24b5eed6e8999500c5fae1d8bfe9d991d23f77
diff --git a/Android.bp b/Android.bp
index a1528c4..0b867ed 100644
--- a/Android.bp
+++ b/Android.bp
@@ -29,6 +29,8 @@
         proguard_flags_files: ["proguard.flags"],
     },
 
+    product_specific: true,
+
     static_libs: [
         "cr",
         "androidx.legacy_legacy-support-v4",