Fix following WiFi bugs:
1. Fix the bug that wpa2 enterprise sta can connect open AP
2. Fix TKIP/CCMP PN replay attack detection bug
3. Increase buffer number type from uint8_t to uint16_t to support more than 255 buffers
4. Avoid recalculating PMK if esp_wifi_set_config() is not called
5. Fix the bug that scan done leads to crash because of uint8 overflow
6. Fix 5.5M signal test bug