irqchip/renesas-rzg2l: Convert to irq_data_get_irq_chip_data()

Use the existing irq_data_get_irq_chip_data() helper instead of
open-coding the same operation.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/8e47cc6400e5a82c854c855948d2665a3a3197e3.1695819391.git.geert+renesas@glider.be

drivers/irqchip/irq-renesas-rzg2l.c

@@ -130,8 +130,8 @@ static void rzg2l_irqc_irq_enable(struct irq_data *d)
 	unsigned int hw_irq = irqd_to_hwirq(d);
 
 	if (hw_irq >= IRQC_TINT_START && hw_irq < IRQC_NUM_IRQ) {
+		unsigned long tint = (uintptr_t)irq_data_get_irq_chip_data(d);
 		struct rzg2l_irqc_priv *priv = irq_data_to_priv(d);
-		unsigned long tint = (uintptr_t)d->chip_data;
 		u32 offset = hw_irq - IRQC_TINT_START;
 		u32 tssr_offset = TSSR_OFFSET(offset);
 		u8 tssr_index = TSSR_INDEX(offset);