Merge branch 'bugfix/strict_prototypes' into 'master'

Enable strict prototypes checks

Closes IDFGH-757

See merge request espressif/esp-idf!4546

diff --cc examples/bluetooth/bluedroid/ble/ble_ancs/main/ble_ancs_demo.c
Simple merge

diff --cc examples/protocols/esp_local_ctrl/main/app_main.c
Simple merge

diff --cc examples/storage/ext_flash_fatfs/main/ext_flash_fatfs_example_main.c
Simple merge

diff --cc examples/wifi/power_save/main/power_save.c
Simple merge