scsi: aic79xx: Remove redundant error variable

Return the value from ahd_linux_queue_abort_cmd() directly instead of using
a redundant variable.

Link: https://lore.kernel.org/r/20220104112452.601899-1-chi.minghao@zte.com.cn


Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Minghao Chi <chi.minghao@zte.com.cn>
Signed-off-by: CGEL ZTE <cgel.zte@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>