WiFi: Add support for ESP32S2

1) Update WiFi and PHY libs for ESP32S2.
2) Remove KConfig options ESP32S2 PHY lib selection.
3) Change target macros from ESP32S2BETA to ESP32S2

components/esp_wifi/include/esp_private/wifi_os_adapter.h

@@ -107,7 +107,7 @@ typedef struct {
     int32_t (* _get_random)(uint8_t *buf, size_t len);
     int32_t (* _get_time)(void *t);
     unsigned long (* _random)(void);
-#if CONFIG_IDF_TARGET_ESP32S2BETA
+#if CONFIG_IDF_TARGET_ESP32S2
     uint32_t (* _slowclk_cal_get)(void);
 #endif
     void (* _log_write)(uint32_t level, const char* tag, const char* format, ...);