Support CompOS Key Service in a VM

Add the ability to start the service in a VM, and to then communicate
with it from the host via RPC Binder. Update command-line syntax.

Also revert my recent client naming change, since one tool that can
handle both host & VM seems better than two different ones.

Bug: 193603140
Test: Manual: start service in VM, connect to it, generate & verify keys.
Change-Id: I3cdb25395537e29bbfaa957eeac0c16ba4de93de
diff --git a/compos/compos_key_cmd/Android.bp b/compos/compos_key_cmd/Android.bp
index 460b96f..00d1035 100644
--- a/compos/compos_key_cmd/Android.bp
+++ b/compos/compos_key_cmd/Android.bp
@@ -14,6 +14,7 @@
     shared_libs: [
         "compos_aidl_interface-ndk_platform",
         "libbase",
+        "libbinder_rpc_unstable",
         "libbinder_ndk",
         "libcrypto",
         "libfsverity",