nvs_flash_init may return an error code in some cases, and applications
should check this error code (or at least assert on it being ESP_OK, to
make potential issues more immediately obvious).
This change modifies all the examples which use NVS to check the error
code. Most examples get a simple ESP_ERROR_CHECK assert, while NVS
examples, OTA example, and NVS unit tests get a more verbose check which
may be used in real applications.
1. indicate adv/scan start complete success or failed
2. controller do limit of adv/scan concurrence, so add some codes to report adv/scan start failed or not.
1. add new APIs bt controller enable/disab/deinit
2. make bt controller work need to call two APIs of esp_bt_controller_init and enable
3. modify phy init to make mac reset once
In the existing tree, after a connected client disconnects the device
will never re-enter the advertising state. Additional clients will not
be able to discover or connect to the device. This patch forces the
device back into the advertising state upon disconnection.
Resolves Pull Request #217https://github.com/espressif/esp-idf/pull/217
