Disable CR-adding when transferring files via XModem (#528)

* Disable CR-adding when transferring files via XModem

The UART channel have the feature for adding extra CR on line feeds enabled which will break the XModem protocol. This fix will disable the extra CR adding and restore the setting after the file is sent.

* Changed variable name to be consistent with other code.

FluidNC/src/ProcessSettings.cpp

@@ -644,8 +644,10 @@ static Error xmodem_send(const char* value, WebUI::AuthenticationLevel auth_leve
         log_info("Cannot open " << value);
         return Error::DownloadFailed;
     }
+    bool oldCr = out.setCr(false);
     log_info("Sending " << value << " via XModem");
     int size = xmodemTransmit(&out, infile);
+    out.setCr(oldCr);
     delete infile;
     if (size >= 0) {
         log_info("Sent " << size << " bytes");