scsi: qla2xxx: Add sysfs node for D-Port Diagnostics AEN data

This patch adds sysfs node to show D-Port diag data.

Link: https://lore.kernel.org/r/20200212214436.25532-4-hmadhani@marvell.com


Signed-off-by: Joe Carnuccio <joe.carnuccio@cavium.com>
Signed-off-by: Himanshu Madhani <hmadhani@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>