feat(lwip): make LWIP TCP rto time configurable

components/lwip/Kconfig

@@ -449,6 +449,13 @@ menu "LWIP"
             help
                 Enable this feature to support TCP window scaling.
 
+        config LWIP_TCP_RTO_TIME
+            int "Default TCP rto time"
+            default 3000
+            help
+                Set default TCP rto time for a reasonable initial rto.
+                In bad network environment, recommend set value of rto time to 1500.
+
     endmenu # TCP
 
     menu "UDP"

components/lwip/lwip

@@ -1 +1 @@
-Subproject commit 50e4e0d1821a6e5deab0ead9f35ffb4e60625ea6
+Subproject commit 64b640ecae5a6ce510814944d75e9ff408d3fc8d

components/lwip/port/esp32/include/lwipopts.h

@@ -376,6 +376,12 @@
 #define TCP_RCV_SCALE                   CONFIG_LWIP_TCP_RCV_SCALE
 #endif
 
+/**
+ * LWIP_TCP_RTO_TIME: TCP rto time.
+ * Default is 3 second.
+ */
+#define LWIP_TCP_RTO_TIME             CONFIG_LWIP_TCP_RTO_TIME
+
 /*
    ----------------------------------
    ---------- Pbuf options ----------