Bind QLowEnergyController to a particular local adapter.

This simplifies the internal LEServiceInfo logic and let's us later deal
with multiple adapters.

Change-Id: I7d3e991207cd6571b5d644ae99c6bf1a2c99ec68
Reviewed-by: Nedim Hadzic <nhadzic@blackberry.com>
Reviewed-by: Alex Blasche <alexander.blasche@digia.com>