List of changes:
* Use 128 bit characteristic UUIDs when creating GATT table entries
* Change primary service attribute value to 128 bit custom service UUID
* Use raw advertisement data to convey flags and 128 bit primary service UUID
* Use raw scan response to send device name as complete local name
* Increase maximum device name length in relation to maximum scan response length
* Set Characteristic User Description attributes for each characteristic to convey protocomm endpoint names
1. Pass the correct conn_id to protocomm_req_handle
In transport_simple_ble_write(), passing param->exec_write.conn_id would
be invalid. Instead param->write.conn_id should be passed
Similar change in transport_simple_ble_exec_write() to use
param->exec_write.conn_id
2. simple_ble_start() assumes that the mode is BLE only and enables
Bluetooth controller accordingly. For, cases having BT + BLE like Alexa
(Provisioning over BLE + Audio over classic BT), this assumption should
be removed.