[SCSI] hpsa: make hpsa_find_memory_BAR not require the per HBA structure.

Rationale for this is that in order to fix the hard reset code used
by kdump, we need to use this function before we even have the per
HBA structure.

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