ide: allow host drivers to specify IRQ flags

* Add ->irq_flags field to struct ide_port_info and struct ide_host.

* Update host drivers and IDE PCI code to use ->irq_flags field.

* Convert init_irq() and ide_intr() to use host->irq_flags.

This fixes handling of shared IRQs for non-PCI hosts
and removes ugly ifdeffery from core IDE code.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

drivers/ide/scc_pata.c

@@ -891,6 +891,7 @@ static const struct ide_port_info scc_chipset __devinitdata = {
 	.port_ops	= &scc_port_ops,
 	.dma_ops	= &scc_dma_ops,
 	.host_flags	= IDE_HFLAG_SINGLE,
+	.irq_flags	= IRQF_SHARED,
 	.pio_mask	= ATA_PIO4,
 };