Fix error message for invalid voting addresses (#2747)

Author: codablock

src/rpc/rpcevo.cpp

@@ -697,7 +697,7 @@ UniValue protx_update_registrar(const JSONRPCRequest& request)
         ptx.pubKeyOperator = ParseBLSPubKey(request.params[2].get_str(), "operator BLS address");
     }
     if (request.params[3].get_str() != "") {
-        ptx.keyIDVoting = ParsePubKeyIDFromAddress(request.params[3].get_str(), "operator address");
+        ptx.keyIDVoting = ParsePubKeyIDFromAddress(request.params[3].get_str(), "voting address");
     }
 
     CBitcoinAddress payoutAddress(request.params[4].get_str());