[SCSI] zfcp: fix: use correct req_id in eh_abort_handler

zfcp's eh_abort_handler used the wrong request ID to
identify the request to be aborted. The bug was introduced
with commit fea9d6c7
for improved management of request IDs. The bug is
fixed with this patch.

Signed-off-by: Andreas Herrmann <aherrman@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>