scsi: cxlflash: Avoid double free of character device

The device_unregister() service used when cleaning up the character
device is already responsible for the internal state associated with the
device upon successful creation. As the cxlflash driver does not obtain
a second reference to the character device, the explicit call to
put_device() is not required and can lead to an inconsistent sysfs among
other issues as the reference is no longer valid after the first
put_device() is performed.

Remove the unnecessary put_device() to remedy this issue.

Fixes: a834a36b ("scsi: cxlflash: Create character device to provide host management interface")
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>