arm64/smp: Use irq_desc_kstat_cpu() in arch_show_interrupts()

The irq descriptor is already there, no need to look it up again.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20201210194043.546326568@linutronix.de

arch/arm64/kernel/smp.c

@@ -810,7 +810,7 @@ int arch_show_interrupts(struct seq_file *p, int prec)
 		seq_printf(p, "%*s%u:%s", prec - 1, "IPI", i,
 			   prec >= 4 ? " " : "");
 		for_each_online_cpu(cpu)
-			seq_printf(p, "%10u ", kstat_irqs_cpu(irq, cpu));
+			seq_printf(p, "%10u ", irq_desc_kstat_cpu(ipi_desc[i], cpu));
 		seq_printf(p, "      %s\n", ipi_types[i]);
 	}