[SCSI] hpsa: use ioremap_nocache instead of ioremap

I think ioremap() ends up being equivalent to ioremap_nocache
by default, but we should signal our intent that these mappings
should be non-cacheable.

Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>