scsi: qedi: Add schedule_hw_err_handler callback for fan failure

On fan failure event from MFW, bring down active connections and unload
the firmware context.

Link: https://lore.kernel.org/r/20200924070338.8270-1-mrangankar@marvell.com


Signed-off-by: Manish Rangankar <mrangankar@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>