lwip: fix building without TCP_QUEUE_OOSEQ

Author: ourairquality

lwip/esp_interface.c

@@ -164,6 +164,8 @@ void pp_recycle_rx_pbuf(struct pbuf *p)
 
 #define COPY_PP_RX_PBUFS 0
 
+#if TCP_QUEUE_OOSEQ
+
 /* Return the number of ooseq bytes that can be retained given the current
  * size 'n'. */
 size_t ooseq_bytes_limit(struct tcp_pcb *pcb)
@@ -220,6 +222,8 @@ size_t ooseq_pbufs_limit(struct tcp_pcb *pcb)
     return target;
 }
 
+#endif /* TCP_QUEUE_OOSEQ */
+
 /**
  * This function should be called when a packet is ready to be read
  * from the interface. It uses the function low_level_input() that