scsi: MAINTAINERS: Make Xiang Chen HiSilicon SAS controller driver maintainer

I am soon leaving Huawei, so will no longer maintain this driver. However I
will stay active in upstream Linux storage domain.

Xiang Chen has worked on the driver for as long as I have and has good
knowledge of the driver, so should do a good job.
Signed-off-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/1666784008-125519-1-git-send-email-john.garry@huawei.comSigned-off-by: Martin K. Petersen <martin.petersen@oracle.com>

MAINTAINERS

@@ -9290,7 +9290,7 @@ F:	Documentation/devicetree/bindings/infiniband/hisilicon-hns-roce.txt
 F:	drivers/infiniband/hw/hns/
 
 HISILICON SAS Controller
-M:	John Garry <john.garry@huawei.com>
+M:	Xiang Chen <chenxiang66@hisilicon.com>
 S:	Supported
 W:	http://www.hisilicon.com
 F:	Documentation/devicetree/bindings/scsi/hisilicon-sas.txt