scsi: ips: properly handle 64-bit DMA

CONFIG_HIGHMEM64 is only one (and these days unusual) way to indicate
that > 32-bit dma address are possible.  Replace it with a check of the
dma_addr_t size.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/ips.c

@@ -6926,7 +6926,7 @@ ips_init_phase1(struct pci_dev *pci_dev, int *indexPtr)
 	 * it!  Also, don't use 64bit addressing if dma addresses
 	 * are guaranteed to be < 4G.
 	 */
-	if (IPS_ENABLE_DMA64 && IPS_HAS_ENH_SGLIST(ha) &&
+	if (sizeof(dma_addr_t) > 4 && IPS_HAS_ENH_SGLIST(ha) &&
 	    !dma_set_mask(&ha->pcidev->dev, DMA_BIT_MASK(64))) {
 		(ha)->flags |= IPS_HA_ENH_SG;
 	} else {

drivers/scsi/ips.h

@@ -96,12 +96,6 @@
       #define __iomem
    #endif
 
-   #if (BITS_PER_LONG > 32) || defined(CONFIG_HIGHMEM64G)
-      #define IPS_ENABLE_DMA64        (1)
-   #else
-      #define IPS_ENABLE_DMA64        (0)
-   #endif
-
    /*
     * Adapter address map equates
     */