irqchip/gic-v2m: Fix refcount leak in gicv2m_of_init()

gicv2m_of_init() fails to perform an of_node_put() when
of_address_to_resource() fails, leading to a refcount leak.

Address this by moving the error handling path outside of the loop and
making it common to all failure modes.

Fixes: 4266ab1a8ff5 ("irqchip/gic-v2m: Refactor to prepare for ACPI support")
Signed-off-by: Ma Ke <make24@iscas.ac.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20240820092843.1219933-1-make24@iscas.ac.cn
diff --git a/drivers/irqchip/irq-gic-v2m.c b/drivers/irqchip/irq-gic-v2m.c
index 51af63c..be35c53 100644
--- a/drivers/irqchip/irq-gic-v2m.c
+++ b/drivers/irqchip/irq-gic-v2m.c
@@ -407,12 +407,12 @@ static int __init gicv2m_of_init(struct fwnode_handle *parent_handle,
 
 		ret = gicv2m_init_one(&child->fwnode, spi_start, nr_spis,
 				      &res, 0);
-		if (ret) {
-			of_node_put(child);
+		if (ret)
 			break;
-		}
 	}
 
+	if (ret && child)
+		of_node_put(child);
 	if (!ret)
 		ret = gicv2m_allocate_domains(parent);
 	if (ret)