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__ */

components/lwip/port/esp32/include/debug/lwip_debug.h

@@ -16,10 +16,18 @@
 #ifndef _LWIP_DEBUG_H
 #define _LWIP_DEBUG_H
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 void dbg_lwip_tcp_pcb_show(void);
 void dbg_lwip_udp_pcb_show(void);
 void dbg_lwip_tcp_rxtx_show(void);
 void dbg_lwip_udp_rxtx_show(void);
 void dbg_lwip_mem_cnt_show(void);
 
+#ifdef __cplusplus
+}
 #endif
+
+#endif // _LWIP_DEBUG_H

tools/ci/check_public_headers_exceptions.txt

@@ -29,9 +29,6 @@ components/lwip/include/apps/dhcpserver/dhcpserver_options.h
 components/lwip/include/apps/dhcpserver/dhcpserver.h
 
 components/lwip/lwip/src/include/lwip/priv/memp_std.h
-components/lwip/port/esp32/include/arch/cc.h
-components/lwip/port/esp32/include/debug/lwip_debug.h
-components/lwip/port/esp32/include/arch/cc.h
 
 components/vfs/include/sys/dirent.h