block: remove the unused blk_bounce enum

The enum has been replaced with the BLK_FEAT_BOUNCE_HIGH flag.

Reported-by: Keith Busch <[e-mail]>
Signed-off-by: Christoph Hellwig <[e-mail]>
Reviewed-by: Martin K. Petersen <[e-mail]>
Reviewed-by: Johannes Thumshirn <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Jens Axboe <[e-mail]>

include/linux/blkdev.h

···
 	BLK_FLAGS_WRITE_CACHE_DISABLED		= (1u << 31),
 };
 
-/*
- * BLK_BOUNCE_NONE:	never bounce (default)
- * BLK_BOUNCE_HIGH:	bounce all highmem pages
- */
-enum blk_bounce {
-	BLK_BOUNCE_NONE,
-	BLK_BOUNCE_HIGH,
-};
-
 struct queue_limits {
 	unsigned int		features;
 	unsigned int		flags;