Add a CLI driver for compos_key_service.

This will eventually go away, but it's useful for verifying that the
service is working. But the cert -> RSAPublicKey code will end up
somewhere else eventually - either in C++ or Rust.

Bug: 191763370
Test: Manual - start service, generate key, verify. Inspect files.
Change-Id: I2181cf5331992a4236500545a9fdfd8640b57c1d
diff --git a/compos/compos_key_cmd/Android.bp b/compos/compos_key_cmd/Android.bp
new file mode 100644
index 0000000..e03dfdf
--- /dev/null
+++ b/compos/compos_key_cmd/Android.bp
@@ -0,0 +1,16 @@
+package {
+    default_applicable_licenses: ["Android-Apache-2.0"],
+}
+
+cc_binary {
+    name: "compos_key_cmd",
+    srcs: ["compos_key_cmd.cpp"],
+    apex_available: ["com.android.virt"],
+
+    shared_libs: [
+        "compos_aidl_interface-ndk_platform",
+        "libbase",
+        "libbinder_ndk",
+        "libcrypto",
+    ],
+}