irqchip/renesas-irqc: Replace irqc_priv.pdev by irqc_priv.dev

Nothing really uses irqc_priv.pdev, all users need irqc_priv.pdev->dev.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>