Add small binary performing the SDP scan.

This is required to avoid tainting of QtBluetooth with GPL code from
Bluez.

Subsequent patches will remove GPL code from the new Bluez5 backend
in the library and call this binary instead.

Change-Id: Iff62ecb430d4a486a2d1f7382ba5dc48b229fea5
Reviewed-by: Aaron McCarthy <mccarthy.aaron@gmail.com>