This micro-optimization is not worth it.  Just always check for
existence of ->ack_intr method in ide_intr() and ide_timer_expiry().
v2:
Fix brown-paper-bag bug spotted by David D. Kilzer.
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michael Schmitz <schmitz@debian.org>
Cc: "David D. Kilzer" <ddkilzer@kilzer.net>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
 }
 #endif /* CONFIG_BLK_DEV_FALCON_IDE */
 
-#define IDE_ARCH_ACK_INTR
-#define ide_ack_intr(hwif)     ((hwif)->ack_intr ? (hwif)->ack_intr(hwif) : 1)
-
 #endif /* __KERNEL__ */
 #endif /* _M68K_IDE_H */
 
                } else if (drive_is_ready(drive)) {
                        if (drive->waiting_for_dma)
                                hwif->dma_ops->dma_lost_irq(drive);
-                       (void)ide_ack_intr(hwif);
+                       if (hwif->ack_intr)
+                               hwif->ack_intr(hwif);
                        printk(KERN_WARNING "%s: lost interrupt\n",
                                drive->name);
                        startstop = handler(drive);
 
        spin_lock_irqsave(&hwif->lock, flags);
 
-       if (!ide_ack_intr(hwif))
+       if (hwif->ack_intr && hwif->ack_intr(hwif) == 0)
                goto out;
 
        handler = hwif->handler;
 
 
 #define MAX_HWIFS      10
 
-/* Currently only m68k, apus and m8xx need it */
-#ifndef IDE_ARCH_ACK_INTR
-# define ide_ack_intr(hwif) (1)
-#endif
-
 /* Currently only Atari needs it */
 #ifndef IDE_ARCH_LOCK
 # define ide_release_lock()                    do {} while (0)