ide: move ide_rate_filter() calls to the upper layer (take 2)

* Move ide_rate_filter() calls from host drivers to IDE core.

* Make ide_rate_filter() static.

* Make 'speed' argument of ->speedproc const.

v2:
* Fix it8213_tune_chipset() comment.

There should be no functionality changes caused by this patch.

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
diff --git a/drivers/ide/pci/it8213.c b/drivers/ide/pci/it8213.c
index 70b3245..6fa9557 100644
--- a/drivers/ide/pci/it8213.c
+++ b/drivers/ide/pci/it8213.c
@@ -115,20 +115,16 @@
 /**
  *	it8213_tune_chipset	-	set controller timings
  *	@drive: Drive to set up
- *	@xferspeed: speed we want to achieve
+ *	@speed: speed we want to achieve
  *
- *	Tune the ITE chipset for the desired mode. If we can't achieve
- *	the desired mode then tune for a lower one, but ultimately
- *	make the thing work.
+ *	Tune the ITE chipset for the desired mode.
  */
 
-static int it8213_tune_chipset (ide_drive_t *drive, u8 xferspeed)
+static int it8213_tune_chipset(ide_drive_t *drive, const u8 speed)
 {
-
 	ide_hwif_t *hwif	= HWIF(drive);
 	struct pci_dev *dev	= hwif->pci_dev;
 	u8 maslave		= 0x40;
-	u8 speed		= ide_rate_filter(drive, xferspeed);
 	int a_speed		= 3 << (drive->dn * 4);
 	int u_flag		= 1 << drive->dn;
 	int v_flag		= 0x01 << drive->dn;