When sending "SLEEP" command to the controller it ceases scanning
completely and is unable to wake the system up from sleep, so if it is
configured as a wakeup source we should simply configure interrupt for
wakeup and rely on idle logic within the controller to reduce power
consumption while it is not used.
Signed-off-by: NJames Chen <james.chen@emc.com.tw>
Signed-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>