scsi: libsas: Do not export sas_ata_wait_after_reset()

sas_ata_wait_after_reset() does not need to be exported since it is no
longer referenced outside libsas.

Signed-off-by: Jie Zhan <zhanjie9@hisilicon.com>
Link: https://lore.kernel.org/r/20221118083714.4034612-6-zhanjie9@hisilicon.com
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>