sepolicy: fix 28.0.ignore.cil build

29.0.ignore.cil/29.0.cil should be expanded into
28.0.ignore.cil/28.0.cil, so that there is no need to duplicate changes
in both places.

Test: adding a type to 29.0.ignore.cil/29.0.cil only doesn't trigger a
build error.
Change-Id: I543c0fc5e3749211e5bede81aabb0b520435a510
diff --git a/Android.bp b/Android.bp
index bf91041..e1b57a5 100644
--- a/Android.bp
+++ b/Android.bp
@@ -109,7 +109,7 @@
 se_cil_compat_map {
     name: "28.0.ignore.cil",
     bottom_half: [":28.0.board.ignore.map"],
-    // top_half: "29.0.ignore.cil",
+    top_half: "29.0.ignore.cil",
 }
 
 se_cil_compat_map {