Secretkeeper implementation: in-HAL/nonsecure impl

Create the default/reference implementation of Secretkeeper HAL. Status
quo, this is non-secure implementation. In reality, the HAL should be
backed by a privileged component such a trusted app.

Bug: 291224769
Test: Topic includes VTS
Change-Id: I6a4ad50482d537f5438de6201275f4020cd827df
diff --git a/compatibility_matrices/compatibility_matrix.9.xml b/compatibility_matrices/compatibility_matrix.9.xml
index 83d2665..9f6b78b 100644
--- a/compatibility_matrices/compatibility_matrix.9.xml
+++ b/compatibility_matrices/compatibility_matrix.9.xml
@@ -302,6 +302,14 @@
             <instance>default</instance>
         </interface>
     </hal>
+    <hal format="aidl" optional="true">
+        <name>android.hardware.security.secretkeeper</name>
+        <version>1</version>
+        <interface>
+            <name>ISecretkeeper</name>
+            <instance>nonsecure</instance>
+        </interface>
+    </hal>
     <hal format="aidl" optional="true" updatable-via-apex="true">
         <name>android.hardware.security.keymint</name>
         <version>1-3</version>