[SCSI] ipr: fix lun assignment and comparison

The lun value was not getting set up correctly for all devices attached to the
new 64 bit adapters.  The fix is to move the logic to earlier in the
ipr_init_res_entry routine such that the value does get set correctly for all
devices.

Then the ipr_is_same_device comparison function was using the wrong lun value
in the logic for the new adapters.  Change this to use the correct lun value.

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>