Release of BlueZ 5.48

This is a long due release which brings many fixes and feature enhancements. Some notable enhancements include support for devices with the BLE battery service, as well as improved Mesh support in the meshctl tool. Several previously experimental D-Bus APIs have now been marked as stable, notably the Advertising Manager API as well as the AquireWrite & AquireNotify GATT APIs.

As far as fixes go, these can be found in many areas of the stack, including A2DP, AVCTP, device discovery, Mesh, and GATT.