1. bluedroid: use standard function pointer define.
2. blufi: Change ESP_BD_ADDR_LEN into ESP_BLUFI_BD_ADDR_LEN
3. doc/sphinx_known_warnings: Remove fixed parts.
- Adds HID Host support in Buedroid
- Adds BLE HID Host and Device support
- Adds some general HID utilities and definitions to help integrate with other stacks and native USB