scsi: hisi_sas: enable use_clustering

driver inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5B468


CVE: NA

------------------------------------------------

Enable "clustering", that is merging of segments so that they might span
more than a single page, and optimized the issue that 520 KB of service
delivery is split.

fio test with --filename=/dev/sdb --bs=520k --iodepth=32

before:
[root@localhost ~]# cat /sys/block/sdb/queue/max_segment_size
4096

[root@localhost ~]#iostat -x
Device ... r_await rareq-sz ... aqu-sz  %util
sdb    ... 29.78   259.89   ... 5.87    9.92

after:
[root@localhost ~]# cat /sys/block/sdb/queue/max_segment_size
65536

[root@localhost ~]#iostat -x
Device ... r_await rareq-sz ... aqu-sz  %util
sdb    ... 29.80   516.03   ... 1.34    4.50

Signed-off-by: Xingui Yang <yangxingui@huawei.com>
Reviewed-by: kang fenglong <kangfenglong@huawei.com>
Acked-by: Xie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: Laibin Qiu <qiulaibin@huawei.com>