Limit visibility of libfmq_rust while under development am: 4bbbba517a

Original change: https://android-review.googlesource.com/c/platform/system/libfmq/+/3118152

Change-Id: Id327ddb119b22175599685bc2bf08ed1d6e4d336
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

Android.bp

diff --git a/Android.bp b/Android.bp
index cd8c2b3..ae4e6b0 100644
--- a/Android.bp
+++ b/Android.bp
@@ -104,6 +104,7 @@
     crate_name: "fmq_bindgen",
     edition: "2021",
     host_supported: true,
+    visibility: [":__subpackages__"],
     source_stem: "fmq",
     bindgen_flags: [
         "--no-recursive-allowlist",
@@ -187,6 +188,7 @@
 rust_library {
     name: "libfmq_rust",
     host_supported: true,
+    visibility: [":__subpackages__"],
     crate_name: "fmq",
     srcs: ["libfmq.rs"],
     edition: "2021",