Merge branch 'feature/set_11g_mode_by_default' into 'master'

feat(lib): set 11g mode by default

See merge request sdk/ESP8266_RTOS_SDK!701

Author: wujiangang

components/esp8266/lib/VERSION

@@ -1,6 +1,6 @@
 gwen:
     core:       5550687
-    net80211:   16e1df2
+    net80211:   8a7bbdb
     pp:         957ad08
     wpa:        4e2372f
     espnow:     eeb16c6