irqchip/loongson-pch-pic: Fix potential incorrect hwirq assignment

In DeviceTree path, when ht_vec_base is not zero, the hwirq of PCH PIC
will be assigned incorrectly. Because when pch_pic_domain_translate()
adds the ht_vec_base to hwirq, the hwirq does not have the ht_vec_base
subtracted when calling irq_domain_set_info().

The ht_vec_base is designed for the parent irq chip/domain of the PCH PIC.
It seems not proper to deal this in callbacks of the PCH PIC domain and
let's put this back like the initial commit ef8c01e ("irqchip: Add
Loongson PCH PIC controller").

Fixes: bcdd75c ("irqchip/loongson-pch-pic: Add ACPI init support")
Cc: stable@vger.kernel.org
Reviewed-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Liu Peibao <liupeibao@loongson.cn>
Signed-off-by: Jianmin Lv <lvjianmin@loongson.cn>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230614115936.5950-3-lvjianmin@loongson.cn

Author: Liu Peibao

drivers/irqchip/irq-loongson-pch-pic.c

@@ -164,7 +164,7 @@ static int pch_pic_domain_translate(struct irq_domain *d,
 		if (fwspec->param_count < 2)
 			return -EINVAL;
 
-		*hwirq = fwspec->param[0] + priv->ht_vec_base;
+		*hwirq = fwspec->param[0];
 		*type = fwspec->param[1] & IRQ_TYPE_SENSE_MASK;
 	} else {
 		if (fwspec->param_count < 1)
@@ -196,7 +196,7 @@ static int pch_pic_alloc(struct irq_domain *domain, unsigned int virq,
 
 	parent_fwspec.fwnode = domain->parent->fwnode;
 	parent_fwspec.param_count = 1;
-	parent_fwspec.param[0] = hwirq;
+	parent_fwspec.param[0] = hwirq + priv->ht_vec_base;
 
 	err = irq_domain_alloc_irqs_parent(domain, virq, 1, &parent_fwspec);
 	if (err)