hpsa: choose number of reply queues more intelligently.

No sense having 8 or 16 reply queues if you only have 4 cpus,
and likewise no sense limiting to 8 reply queues if you have
many more cpus.

Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Reviewed-by: Mike Miller <michael.miller@canonical.com>
Reviewed-by: Scott Teel <scott.teel@hp.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>