usb: ehci-orion: use platform_get_irq() for DT probing

Commit 77dae54a ('ARM: Kirkwood:
ehci-orion: Add device tree binding') added the Device Tree binding
for the ehci-orion driver. To achieve that with the irq, it used the
irq_of_parse_and_map() function when probed in DT-mode, and
platform_get_irq() when probed in non-DT mode.

This is not necessary: platform_get_irq() works just as fine in
DT-mode, since the conversion from DT information to 'struct resource'
is done by the generic layers of the kernel.

Therefore, this commit switches back to use just platform_get_irq().
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/ehci-orion.c

@@ -154,9 +154,6 @@ static int ehci_orion_drv_probe(struct platform_device *pdev)
 
 	pr_debug("Initializing Orion-SoC USB Host Controller\n");
 
-	if (pdev->dev.of_node)
-		irq = irq_of_parse_and_map(pdev->dev.of_node, 0);
-	else
 	irq = platform_get_irq(pdev, 0);
 	if (irq <= 0) {
 		dev_err(&pdev->dev,