adapter: Remove temporary devices before power off

adapter: Remove temporary devices before power off

If adapter is powered off when a currently connected device is
being removed, there is a possibility that we haven't finish waiting
for the disconnection but the adapter is already powered down.

When this happens, the kernel would fail to clean the device's
information, for example the pairing information. This causes
disagreement between the user space and the kernel about whether the
device is already paired, because the device is successfully removed
from the user space's perspective.

This patch enforces the removal of such devices before allowing the
adapter to power off.

Signed-off-by: Anuj Jain <anuj01.jain@samsung.com>
Signed-off-by: Ayush Garg <ayush.garg@samsung.com>