VM: Introduce writePayloadRpData/readPayloadRpData

VM payload require an api to allow storing n bytes' data with
confidentialty & tamper evidence integrity guarantees.

Microdroid Manager implements this using the vm_secret module, which
uses the payload's DICE chain to store/get secret from Secretkeeper.

Additionally introduce a test that uses these api.
Test: #rollbackProtectedDataOfPayload
Bug: 378911776

Change-Id: Id39f5c6c626531029bf33ef5d28dc237881e40e6
diff --git a/libs/libvm_payload/libvm_payload.map.txt b/libs/libvm_payload/libvm_payload.map.txt
index 3daad00..0c6b56d 100644
--- a/libs/libvm_payload/libvm_payload.map.txt
+++ b/libs/libvm_payload/libvm_payload.map.txt
@@ -15,6 +15,8 @@
     AVmAttestationStatus_toString;       # systemapi introduced=VanillaIceCream
     AVmAttestationResult_getCertificateCount; # systemapi introduced=VanillaIceCream
     AVmAttestationResult_getCertificateAt; # systemapi introduced=VanillaIceCream
+    AVmPayload_writeRollbackProtectedSecret; # systemapi introduced=36
+    AVmPayload_readRollbackProtectedSecret; # systemapi introduced=36
   local:
     *;
 };