[SCSI] ipr: implement fixes for 64 bit adapter support

Implement some small fixes for 64 bit support that were preventing
the adapter from becoming operational.

Signed-off-by: Wayne Boyer <wayneb@linux.vnet.ibm.com>
Acked-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>