esp_wifi: modify WiFi buffer number type from uint8_t to uint16_t

Modify WiFi receiving buffer number type from uint8_t to uint16_t to support
configuring more than 255 buffers.

diff --git a/components/esp_wifi/lib_esp32 b/components/esp_wifi/lib_esp32
index 4f8e1517f53e9aca81cf7b604563b3807df834d9..1068594fee5fd8a73b353c4e77ff3b44d111393d 160000 (submodule)
--- a/components/esp_wifi/lib_esp32
+++ b/components/esp_wifi/lib_esp32
@@ -1 +1 @@
-Subproject commit 4f8e1517f53e9aca81cf7b604563b3807df834d9
+Subproject commit 1068594fee5fd8a73b353c4e77ff3b44d111393d