libata: add another IRQ calls (libata drivers)

This patch is against each libata driver.

Two IRQ calls are added in ata_port_operations.
- irq_on() is used to enable interrupts.
- irq_ack() is used to acknowledge a device interrupt.

In most drivers, ata_irq_on() and ata_irq_ack() are used for
irq_on and irq_ack respectively.

In some drivers (ex: ahci, sata_sil24) which cannot use them
as is, ata_dummy_irq_on() and ata_dummy_irq_ack() are used.

Signed-off-by: Kou Ishizaki <kou.ishizaki@toshiba.co.jp>
Signed-off-by: Akira Iguchi <akira2.iguchi@toshiba.co.jp>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/ata/sata_nv.c b/drivers/ata/sata_nv.c
index b9ef6f5..77e47b7 100644
--- a/drivers/ata/sata_nv.c
+++ b/drivers/ata/sata_nv.c
@@ -362,6 +362,8 @@
 	.data_xfer		= ata_data_xfer,
 	.irq_handler		= nv_generic_interrupt,
 	.irq_clear		= ata_bmdma_irq_clear,
+	.irq_on			= ata_irq_on,
+	.irq_ack		= ata_irq_ack,
 	.scr_read		= nv_scr_read,
 	.scr_write		= nv_scr_write,
 	.port_start		= ata_port_start,
@@ -387,6 +389,8 @@
 	.data_xfer		= ata_data_xfer,
 	.irq_handler		= nv_nf2_interrupt,
 	.irq_clear		= ata_bmdma_irq_clear,
+	.irq_on			= ata_irq_on,
+	.irq_ack		= ata_irq_ack,
 	.scr_read		= nv_scr_read,
 	.scr_write		= nv_scr_write,
 	.port_start		= ata_port_start,
@@ -412,6 +416,8 @@
 	.data_xfer		= ata_data_xfer,
 	.irq_handler		= nv_ck804_interrupt,
 	.irq_clear		= ata_bmdma_irq_clear,
+	.irq_on			= ata_irq_on,
+	.irq_ack		= ata_irq_ack,
 	.scr_read		= nv_scr_read,
 	.scr_write		= nv_scr_write,
 	.port_start		= ata_port_start,
@@ -439,6 +445,8 @@
 	.data_xfer		= ata_data_xfer,
 	.irq_handler		= nv_adma_interrupt,
 	.irq_clear		= nv_adma_irq_clear,
+	.irq_on			= ata_irq_on,
+	.irq_ack		= ata_irq_ack,
 	.scr_read		= nv_scr_read,
 	.scr_write		= nv_scr_write,
 	.port_start		= nv_adma_port_start,