Clean warnings when all warning enabled (#2112)

* Clean warnings when all warning enabled

Not used variables / functions due to debug log

Dual define with different values :
cores\esp32/binary.h
#define B110 6
#define B1000000 64

tools/sdk/include/newlib/sys/termios.h
#define B110        3
#define B1000000   23

Local variable returned in WiFiclient Secure

* change due to deprecated function

* Update with proper variable and label

* Update esp32-hal-i2c.c

* Apply changes requested

* Fix warnings due to #define conflict thanks @atanisoft

libraries/WiFi/src/WiFiClient.cpp

@@ -439,6 +439,9 @@ uint8_t WiFiClient::connected()
     if (_connected) {
         uint8_t dummy;
         int res = recv(fd(), &dummy, 0, MSG_DONTWAIT);
+        if(res < 0) {
+            log_e("RES: %d", res);
+        }
         switch (errno) {
             case EWOULDBLOCK:
             case ENOENT: //caused by vfs