soc: microchip: mpfs-sys-controller: fix resource leak on probe error

In mpfs_sys_controller_probe(), when device_get_match_data() returns
NULL, it returns -EINVAL directly without freeing the mbox channel
or the allocated sys_controller memory, causing a resource leak.

Fixes: 63b5305ad8 ("soc: microchip: mpfs-sys-controller: add support for pic64gx")
Signed-off-by: Felix Gu <ustc.gu@gmail.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>

drivers/soc/microchip/mpfs-sys-controller.c

@@ -158,8 +158,8 @@ no_flash:
 
 	of_data = (struct mpfs_syscon_config *) device_get_match_data(dev);
 	if (!of_data) {
-		dev_err(dev, "Error getting match data\n");
-		return -EINVAL;
+		ret = dev_err_probe(dev, -EINVAL, "Error getting match data\n");
+		goto out_free_channel;
 	}
 
 	for (i = 0; i < of_data->nb_subdevs; i++) {
@@ -173,6 +173,8 @@ no_flash:
 
 	return 0;
 
+out_free_channel:
+	mbox_free_channel(sys_controller->chan);
 out_free:
 	kfree(sys_controller);
 	return ret;