mailbox: Use dev_fwnode()

irq_domain_create_simple() takes fwnode as the first argument. It can be
extracted from the struct device using dev_fwnode() helper instead of
using of_node with of_fwnode_handle().

So use the dev_fwnode() helper.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Cc: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Cc: Jassi Brar <jassisinghbrar@gmail.com>
Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com>

Author: Jiri Slaby (SUSE)

drivers/mailbox/qcom-ipcc.c

@@ -312,8 +312,7 @@ static int qcom_ipcc_probe(struct platform_device *pdev)
 	if (!name)
 		return -ENOMEM;
 
-	ipcc->irq_domain = irq_domain_create_tree(of_fwnode_handle(pdev->dev.of_node),
-						  &qcom_ipcc_irq_ops, ipcc);
+	ipcc->irq_domain = irq_domain_create_tree(dev_fwnode(&pdev->dev), &qcom_ipcc_irq_ops, ipcc);
 	if (!ipcc->irq_domain)
 		return -ENOMEM;