feat(esp8266): make tx rate start from high to low

components/esp8266/Kconfig

@@ -49,6 +49,13 @@ config SCAN_AP_MAX
 
         User can use own function "esp_wifi_scan_get_ap_num_max" to determin how many AP to scan , too.
 
+config WIFI_TX_RATE_SEQUENCE_FROM_HIGH
+    bool "Set wifi tx rate from 54M to 1M"
+    default n
+    help
+        If this option is enabled, Wifi will try to send packets first from high rate(54M). If it fails, it will 
+        try at low rate until the transmission is successful.
+
 endmenu
 
 menu PHY

components/esp8266/source/esp_wifi.c

@@ -56,3 +56,11 @@ size_t __attribute__((weak)) esp_wifi_scan_get_ap_num_max(void)
 {
     return CONFIG_SCAN_AP_MAX;
 }
+
+bool IRAM_ATTR esp_wifi_try_rate_from_high(void) {
+#if CONFIG_WIFI_TX_RATE_SEQUENCE_FROM_HIGH
+    return true;
+#else
+    return false;
+#endif
+}

components/lwip/Kconfig

@@ -10,6 +10,7 @@ config LWIP_HIGH_THROUGHPUT
     select TCP_QUEUE_OOSEQ
     select TCP_HIGH_SPEED_RETRANSMISSION
     select SOC_FULL_ICACHE
+    select WIFI_TX_RATE_SEQUENCE_FROM_HIGH
     help
         Enable this option, also enable "TCP_QUEUE_OOSEQ", "TCP_HIGH_SPEED_RETRANSMISSION" and
         "SOC_FULL_ICACHE", so lwip should cache TCP message received in disorder sequence and