don't set sock_available just to count it back to 0

src/TinyGsmClientBG96.h

@@ -544,12 +544,9 @@ protected:
       return 0;
     }
     size_t len = stream.readStringUntil('\n').toInt();
-    sockets[mux]->sock_available = len;
 
     for (size_t 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
     }
     waitResponse();
     DBG("### READ:", len, "from", mux);

src/TinyGsmClientSaraR4.h

@@ -605,13 +605,10 @@ protected:
     }
     streamSkipUntil(','); // Skip mux
     size_t len = stream.readStringUntil(',').toInt();
-    sockets[mux]->sock_available = len;
     streamSkipUntil('\"');
 
     for (size_t 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
     }
     streamSkipUntil('\"');
     waitResponse();

src/TinyGsmClientSequansMonarch.h

@@ -621,8 +621,6 @@ protected:
       while (!stream.available() && ((millis() - startMillis) < sockets[mux % TINY_GSM_MUX_COUNT]->_timeout)) { TINY_GSM_YIELD(); } \
       char c = stream.read(); \
       sockets[mux % TINY_GSM_MUX_COUNT]->rx.put(c);
-      sockets[mux % TINY_GSM_MUX_COUNT]->sock_available--;
-      // ^^ One less character available after moving from modem's FIFO to our FIFO
     }
     DBG("### Read:", len, "from", mux);
     waitResponse();

src/TinyGsmClientUBLOX.h

@@ -593,13 +593,10 @@ protected:
     }
     streamSkipUntil(','); // Skip mux
     size_t len = stream.readStringUntil(',').toInt();
-    sockets[mux]->sock_available = len;
     streamSkipUntil('\"');
 
     for (size_t 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
     }
     streamSkipUntil('\"');
     waitResponse();