better error handling

Author: Links2004

libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp

@@ -354,7 +354,7 @@ int HTTPClient::sendRequest(const char * type, Stream * stream, size_t size) {
 
     if(buff) {
         // read all data from stream and send it to server
-        while(connected() && (stream->available() != -1) && (len > 0 || len == -1)) {
+        while(connected() && (stream->available() > -1) && (len > 0 || len == -1)) {
 
             // get available data size
             size_t s = stream->available();