update2.html: fix typo (#143)

Author: hmmbob

SmartEVSE-3/data/update2.html

@@ -99,7 +99,7 @@
           Flash one of:<ul>
               <li>firmware.bin or firmware.signed.bin (to update the firmware);</li>
               <li>firmware.debug.bin or firmware.debug.signed.bin (if you want to telnet to your SmartEVSE to see debug messages);</li>
-              <li>rfix.txt (if you want to bulk upload allowed NFC tags for the RFID reader);</li>
+              <li>rfid.txt (if you want to bulk upload allowed NFC tags for the RFID reader);</li>
           </ul>
           You should only flash files with those exact names.<br>No need to flash spiffs.bin for versions 3.6.0-RC1 and newer!<br>No need to rename firmware.debug.bin anymore for versions 3.6.0-RC2 and newer!<br>Signed firmware is verified to be original and can be handled by versions 3.6.2 and newer.
       </div>