[SCSI] libosd: Bugfix of error handling in attributes-list decoding

When an error was detected in an attribute list do to
a target bug. We would print an error but spin endlessly
regardless. Fix it.

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>