scsi: aacraid: Remove an unused include

flush_kernel_dcache_page() is not used by aacraid, and this header already
comes in through the scatterlist/block headers anyway.

Link: https://lore.kernel.org/r/20210712060928.4161649-6-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/aacraid/aachba.c

@@ -25,7 +25,6 @@
 #include <linux/completion.h>
 #include <linux/blkdev.h>
 #include <linux/uaccess.h>
-#include <linux/highmem.h> /* For flush_kernel_dcache_page */
 #include <linux/module.h>
 
 #include <asm/unaligned.h>