irqchip/riscv-rpmi-sysmsi: Fix mailbox channel leak in rpmi_sysmsi_probe()

commit 76f0930 upstream.

When riscv_acpi_get_gsi_info() fails, the mailbox channel previously
requested via mbox_request_channel() is not freed. Add the missing
mbox_free_channel() call to prevent the resource leak.

Fixes: 4752b0c ("irqchip/riscv-rpmi-sysmsi: Add ACPI support")
Signed-off-by: Felix Gu <ustc.gu@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Cc: stable@vger.kernel.org
Reviewed-by: Rahul Pathak <rahul@summations.net>
Link: https://patch.msgid.link/20260315-sysmsi-v1-1-5f090c86c2ca@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: outman119

drivers/irqchip/irq-riscv-rpmi-sysmsi.c

@@ -250,6 +250,7 @@ static int rpmi_sysmsi_probe(struct platform_device *pdev)
 		rc = riscv_acpi_get_gsi_info(fwnode, &priv->gsi_base, &id,
 					     &nr_irqs, NULL);
 		if (rc) {
+			mbox_free_channel(priv->chan);
 			dev_err(dev, "failed to find GSI mapping\n");
 			return rc;
 		}