scsi: mpt3sas: Only one vSES is present even when IOC has multi vSES

scsi: mpt3sas: Only one vSES is present even when IOC has multi vSES

Whenever the driver is adding a vSES to virtual-phys list it is
reinitializing the list head. Hence those vSES devices which were added
previously are lost.

Stop reinitializing the list every time a new vSES device is added.

Link: https://lore.kernel.org/r/20210330105004.20413-1-sreekanth.reddy@broadcom.com
Cc: stable@vger.kernel.org #v5.11.10+
Signed-off-by: Sreekanth Reddy <sreekanth.reddy@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>