irqchip/renesas-rzg2l: Document structure members

Document structure members to follow the requirements specified in
maintainer-tip, section 4.3.7. Struct declarations and initializers.
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20231120111820.87398-5-claudiu.beznea.uj@bp.renesas.com

drivers/irqchip/irq-renesas-rzg2l.c

@@ -56,6 +56,12 @@
 #define TINT_EXTRACT_HWIRQ(x)		FIELD_GET(GENMASK(15, 0), (x))
 #define TINT_EXTRACT_GPIOINT(x)		FIELD_GET(GENMASK(31, 16), (x))
 
+/**
+ * struct rzg2l_irqc_priv - IRQ controller private data structure
+ * @base:	Controller's base address
+ * @fwspec:	IRQ firmware specific data
+ * @lock:	Lock to serialize access to hardware registers
+ */
 struct rzg2l_irqc_priv {
 	void __iomem			*base;
 	struct irq_fwspec		fwspec[IRQC_NUM_IRQ];