protobuf: remove cardano sign/verify messages

protob/messages-cardano.proto

@@ -47,38 +47,6 @@ message CardanoPublicKey {
     optional string root_hd_passphrase = 3;                 // HD passphrase for root in hex format
 }
 
-/**
- * Request: Ask device to sign Cardano message
- * @start
- * @next CardanoMessageSignature
- * @next Failure
- */
-message CardanoSignMessage {
-    repeated uint32 address_n = 1;  // BIP-32 path to derive the key from master node
-    optional bytes message = 2;     // message to be signed
-}
-
-/**
- * Response: Signed Cardano message
- * @end
- */
-message CardanoMessageSignature {
-    optional bytes public_key = 1;  // public key which was used to sign mesage
-    optional bytes signature = 2;   // signature of the message
-}
-
-/**
- * Request: Ask device to verify Cardano message
- * @start
- * @next Success
- * @next Failure
- */
-message CardanoVerifyMessage {
-    optional bytes public_key = 1;  // Public key which was used to sign message
-    optional bytes signature = 2;   // signature to verify
-    optional bytes message = 3;     // message to verify
-}
-
 /**
  * Request: Ask device to sign Cardano transaction
  * @start