irqchip/imx-intmux: Handle pure domain searches correctly

The removal of the paremeter count restriction in the core code to allow
pure domain token based select() decisions broke the IMX intmux select
callback as that unconditioally expects that there is a parameter.

Add the missing check for zero parameter count and the token match.

Fixes: de1ff306dcf4 ("genirq/irqdomain: Remove the param count restriction from select()")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/87ttm3ikok.ffs@tglx

drivers/irqchip/irq-imx-intmux.c

@@ -166,6 +166,10 @@ static int imx_intmux_irq_select(struct irq_domain *d, struct irq_fwspec *fwspec
 	if (fwspec->fwnode != d->fwnode)
 		return false;
 
+	/* Handle pure domain searches */
+	if (!fwspec->param_count)
+		return d->bus_token == bus_token;
+
 	return irqchip_data->chanidx == fwspec->param[1];
 }