scsi: core: clean up generated file scsi_devinfo_tbl.c

"make clean" should remove the generated file "scsi_devinfo_tbl.c", so
list it in the clean-files variable so that the file gets cleaned up.

Fixes: 345e2960 ("scsi: scsi: Export blacklist flags to sysfs")
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>