lwip: Update public port-layer headers with c++ guards, sdkconfig include

This doesn't fix any particular bug, just to meet best practices. Although
including some LWIP headers from C++ files may have caused linker issues.

components/lwip/port/esp32/include/arch/cc.h

@@ -39,8 +39,13 @@
 #include <assert.h>
 #include <stdio.h>
 
+#include "sdkconfig.h"
 #include "arch/sys_arch.h"
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 #ifndef BYTE_ORDER
 #define BYTE_ORDER LITTLE_ENDIAN
 #endif // BYTE_ORDER
@@ -103,5 +108,8 @@ typedef int sys_prot_t;
 
 #endif /* NDEBUG */
 
+#ifdef __cplusplus
+}
+#endif
 
 #endif /* __ARCH_CC_H__ */