pvmfw: Introduce pvmfw_embedded_key

pvmfw contains a reference public key against which it compares the key
used to sign the virtual machine payloads it receives. Export that
public key as pvmfw_embedded_key, a binary file intended to be built
into pvmfw. For release builds, the pvmfw image is expected to be
post-processed to find-and-replace (in-place) that key with the public
release key.

Bug: 255575669
Test: m pvmfw_embedded_key
Change-Id: Ia4490688cc3d1954a18e703a97812a9a28e63e7a
diff --git a/pvmfw/Android.bp b/pvmfw/Android.bp
index d0fc9a9..0872c33 100644
--- a/pvmfw/Android.bp
+++ b/pvmfw/Android.bp
@@ -44,6 +44,12 @@
 }
 
 prebuilt_etc {
+    name: "pvmfw_embedded_key",
+    src: ":avb_testkey_rsa4096_pub_bin",
+    installable: false,
+}
+
+prebuilt_etc {
     name: "pvmfw_sign_key",
     src: ":avb_testkey_rsa4096",
     installable: false,