scsi: ch: Don't use GFP_DMA

The allocated buffers are used as a command payload, for which the block
layer and/or DMA API do the proper bounce buffering if needed.

Link: https://lore.kernel.org/r/20211222090311.916624-1-hch@lst.deSigned-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/ch.c

@@ -239,7 +239,7 @@ ch_read_element_status(scsi_changer *ch, u_int elem, char *data)
 	u_char  *buffer;
 	int     result;
 
-	buffer = kmalloc(512, GFP_KERNEL | GFP_DMA);
+	buffer = kmalloc(512, GFP_KERNEL);
 	if(!buffer)
 		return -ENOMEM;
 
@@ -297,7 +297,7 @@ ch_readconfig(scsi_changer *ch)
 	int     result,id,lun,i;
 	u_int   elem;
 
-	buffer = kzalloc(512, GFP_KERNEL | GFP_DMA);
+	buffer = kzalloc(512, GFP_KERNEL);
 	if (!buffer)
 		return -ENOMEM;
 
@@ -783,7 +783,7 @@ static long ch_ioctl(struct file *file,
 			return -EINVAL;
 		elem = ch->firsts[cge.cge_type] + cge.cge_unit;
 
-		buffer = kmalloc(512, GFP_KERNEL | GFP_DMA);
+		buffer = kmalloc(512, GFP_KERNEL);
 		if (!buffer)
 			return -ENOMEM;
 		mutex_lock(&ch->lock);