lwip/linux: Add lwip support for networking component under linux

linux/lwip: Wrap some IO posix functions
* to workaourd the FreeRTOS EINTR issue (when building without lwip)
* to correctly choose the sub-system based on fd (when building with
lwip) -- passing control to either linux/system or to lwip
This commit also addapts tapio-if to provide DHCP client by default and
configurable settings for static IP

components/lwip/port/linux/include/sys/fcntl.h

@@ -4,9 +4,13 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 #pragma once
-#ifdef LWIP_HDR_ESP_LWIPOPTS_H
-// ignore when included from lwipopts.h since lwip provides all necessary definitions
-#else
-// otherwise include system fcntl
-#include_next <sys/fcntl.h>
+#include "sdkconfig.h"
+
+#ifdef LWIP_HDR_LINUX_SYS_SOCKETS_H
+// only if we prefer linux system sockets, include from system paths
+#include_next <fcntl.h>
+#elif CONFIG_IDF_TARGET_LINUX
+// need to declare, as on linux we bypass IDF vfs and wrap posix io functions
+extern int fcntl(int s, int cmd, ...);
 #endif
+// ignore otherwise (typically included from lwipopts.h) since lwip provides all necessary definitions