Make SignPSBTInput operate on a private SignatureData object

src/wallet/rpcwallet.cpp

@@ -4461,17 +4461,7 @@ bool FillPSBT(const CWallet* pwallet, PartiallySignedTransaction& psbtx, const C
             throw JSONRPCError(RPC_DESERIALIZATION_ERROR, "Specified Sighash and sighash in PSBT do not match.");
         }
 
-        SignatureData sigdata;
-        complete &= SignPSBTInput(HidingSigningProvider(pwallet, !sign, !bip32derivs), *psbtx.tx, input, sigdata, i, sighash_type);
-
-        if (it != pwallet->mapWallet.end()) {
-            // Drop the unnecessary UTXO if we added both from the wallet.
-            if (sigdata.witness) {
-                input.non_witness_utxo = nullptr;
-            } else {
-                input.witness_utxo.SetNull();
-            }
-        }
+        complete &= SignPSBTInput(HidingSigningProvider(pwallet, !sign, !bip32derivs), *psbtx.tx, input, i, sighash_type);
     }
 
     // Fill in the bip32 keypaths and redeemscripts for the outputs so that hardware wallets can identify change