Package the rust_nonsecure keymint default HAL in an APEX

This will make it easier to swap in and out with the Cuttlefish remote
implementation.

Bug: 331474817
Test: m com.android.hardware.keymint.rust_nonsecure
Change-Id: I0e9a350b62a90ef6126db109195e19b4181d0cf8
diff --git a/security/keymint/aidl/default/manifest.json b/security/keymint/aidl/default/manifest.json
new file mode 100644
index 0000000..289943e
--- /dev/null
+++ b/security/keymint/aidl/default/manifest.json
@@ -0,0 +1,5 @@
+{
+    "name": "com.android.hardware.keymint",
+    "version": 1,
+    "vendorBootstrap": true
+}