[SCSI] qla2xxx: Corrections to returned sysfs error codes.

Correct the erroneous return codes introduced by the following patch:
"Return sysfs error codes appropriate to conditions".

Signed-off-by: Joe Carnuccio <joe.carnuccio@qlogic.com>
Signed-off-by: Chad Dupuis <chad.dupuis@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>