d re-enables the Bluetooth USB
device when the switch is flipped back to the 'on' position.

The RFKill switch brute force pulls out the USB device when flipped to
'off', but it doesn't automatically re-enable it. Without this driver,
the Bluetooth is gone until after a reboot on my Portege R500.

Signed-off-by: Jes Sorensen <Jes.Sorensen@gmail.com>
Signed-off-by: Len Brown <len.brown@intel.com>
:¿