neither update last found timestamp nor empty last found value if decoding failed, added decode() for combined master/slave decoding

src/lib/ebus/test/test_message.cpp

@@ -151,9 +151,7 @@ int main()
 		SymbolString writeMstr;
 		if (message->isPassive() == true) {
 			ostringstream output;
-			result = message->decode(pt_masterData, mstr, output);
-			if (result == RESULT_OK)
-				result = message->decode(pt_slaveData, sstr, output, output.str().empty() == false);
+			result = message->decode(mstr, sstr, output);
 			if (result != RESULT_OK) {
 				cout << "  \"" << inputStr << "\": decode error: "
 						<< getResultCode(result) << endl;