Some applications (i.e. Azure IoT SDK) are expecting this header to
exist and to contain the tcp constants and description.
The esp32 did not wrap the lwip/tcp.h header, thus this commit adds a
compatibility layer.
Signed-off-by: Francesco Giancane <francesco.giancane@accenture.com>
Merges https://github.com/espressif/esp-idf/pull/4637
