scsi: libsas: Remove unused declarations

Commit 042ebd29 ("scsi: libsas: kill useless ha_event and do some
cleanup") removed sas_hae_reset() but not its declaration.  Commit
2908d778

 ("[SCSI] aic94xx: new driver") declared but never implemented
other functions.

Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20230809132249.37948-1-yuehaibing@huawei.com
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>