[OTA] Fix "Error response from device" if OK response comes to early

[Gei0r]

Using OTA with platformio, I sometimes get an error like this:

20:14:21 [DEBUG]: Options: {'timeout': 10, 'esp_ip': '192.168.178.45', 'host_port': 44255, 'image': '.pioenvs\\d1_mini\\spiffs.bin', 'host_ip': '0.0.0.0', 'auth': '', 'esp_port': 8266, 'spiffs': True, 'debug': True, 'progress': True}
20:14:21 [INFO]: Starting on 0.0.0.0:44255
20:14:21 [INFO]: Upload size: 1028096
Sending invitation to 192.168.178.45
20:14:21 [INFO]: Waiting for device...
Uploading: [============================================================] 100% Done...

20:14:39 [INFO]: Waiting for result...
20:14:39 [INFO]: Result:
20:14:39 [INFO]: Result:
20:14:39 [INFO]: Result:
20:14:39 [INFO]: Result:
20:14:39 [INFO]: Result:
20:14:39 [ERROR]: Error response from device
*** [uploadfs] Error 1

On investigation I found that the target does send "OK" via TCP. However, espota.py does not receive the OK, because it has been "swallowed up" by an earlier call to recv().

This pull request skips the "wait for OK response" if "OK" has already been received in the last call to recv().

[me-no-dev]

Nice :) Thanks! I've been having this in my to-do list for some time... have not got to it yet :) you saved it!