If we get 0xffff back when reading the status register, assume the card has gone away instead of spinning in the interrupt handler.  This stops my machine from hanging when I eject a rl(4)-based cardbus card.
If we get 0xffff back when reading the status register, assume the card
has gone away instead of spinning in the interrupt handler.  This stops
my machine from hanging when I eject a rl(4)-based cardbus card.

Reviewed by:	imp

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