Oops, fixed some signed/unsigned comparisons

src/TinyGsmClientM95.h

@@ -645,7 +645,7 @@ protected:
     streamSkipUntil(',');  // skip port
     streamSkipUntil(',');  // skip connection type (TCP/UDP)
     int len = stream.readStringUntil('\n').toInt();  // read length
-    for (size_t i=0; i<len; i++) {
+    for (int i=0; i<len; i++) {
       TINY_GSM_MODEM_STREAM_TO_MUX_FIFO_WITH_DOUBLE_TIMEOUT
       sockets[mux]->sock_available--;
       // ^^ One less character available after moving from modem's FIFO to our FIFO