Get the AVRCP Version that the user has requested

This change will grab the user selected AVRCP version number at start up
of the service. This value is a system property and will match the value
the native layer uses in our SDP record. It will allow us to make
decisions on which features to support since some features are not valid
in older versions. Cover art is one such example.

Tag: #feature
Bug: 153076316
Test: atest BluetoothInstrumentationTests
Test: build, flash, make sure proper version appears in dumpsys
bluetooth_manager

Change-Id: I5df51028c47cccc54c1891f5bef259618f254be6