ide: make ide_dma_lost_irq() available also for CONFIG_BLK_DEV_IDEDMA_SFF=n

Make ide_dma_lost_irq() available also for CONFIG_BLK_DEV_IDEDMA_SFF=n
and convert {ics,au1xxx-}ide.c to use it.

While at it:
- use EXPORT_SYMBOL_GPL() to match the rest of SFF DMA functions

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>