irqchip/ti-sci-intr: Fix unsigned comparison to zero

ti_sci_intr_xlate_irq() return -ENOENT on fail, p_hwirq
should be int type.

Fixes: a5b659bd ("irqchip/ti-sci-intr: Add support for INTR being a parent to INTR")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Lokesh Vutla <lokeshvutla@ti.com>
Link: https://lore.kernel.org/r/20200826035321.18620-1-yuehaibing@huawei.com

drivers/irqchip/irq-ti-sci-intr.c

@@ -137,8 +137,8 @@ static int ti_sci_intr_alloc_parent_irq(struct irq_domain *domain,
 	struct ti_sci_intr_irq_domain *intr = domain->host_data;
 	struct device_node *parent_node;
 	struct irq_fwspec fwspec;
-	u16 out_irq, p_hwirq;
-	int err = 0;
+	int p_hwirq, err = 0;
+	u16 out_irq;
 
 	out_irq = ti_sci_get_free_resource(intr->out_irqs);
 	if (out_irq == TI_SCI_RESOURCE_NULL)