[SCSI] ibmvscsi: Handle non SCSI error status

Adds support to the ibmvscsi driver to handle non SCSI error
status. This is needed to support some new VIOS enhancements.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Santiago Leon <santil@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>