scsi: qla2xxx: Use named initializers for q_dev_state

scsi: qla2xxx: Use named initializers for q_dev_state

Make q_dev_state a little more readable and maintainable by using named
initializers.

Also convert QLA8XXX_DEV_* macros into an enum and remove
qla83xx_dev_state_to_string(), which is a duplicate of qdev_state().

Link: https://lore.kernel.org/r/AS8PR10MB495298515A7553C8D6D6E74D9D349@AS8PR10MB4952.EURPRD10.PROD.OUTLOOK.COM
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Gleb Chesnokov <Chesnokov.G@raidix.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>