scsi: qedf: Add comment to display logging levels

Comment will help in decoding the logging level.

Signed-off-by: Saurav Kashyap <skashyap@marvell.com>
Signed-off-by: Chad Dupuis <cdupuis@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>