UPDATE: Back off suspend if repeated attempts fail

If 10 attempts to suspend either fail or immediately resume within
    1 second, back off suspending for 5 seconds multiplied by the
    number of consecutive backoffs.  That is, pause suspends for 5
    seconds after the first 10 failures, 10 seconds after the next
    10 failures, and so on.

    Avoid continually trying to suspend in situations in which a
    driver is repeatedly rejecting suspend or a pending wakeup
    interrupt is not handled, burning CPU in the continuous suspend
    attempts.