power: reset: syscon-reboot: Accept reg property

For historical reasons syscon-reboot has used an 'offset' property. As a
child on a MMIO bus having a 'reg' property is more appropriate. Accept
'reg' as an alternative to 'offset'.

Signed-off-by: Chris Packham <[e-mail]>
Reviewed-by: Krzysztof Kozlowski <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Sebastian Reichel <[e-mail]>

drivers/power/reset/syscon-reboot.c

···
 		priority = 192;
 
 	if (of_property_read_u32(pdev->dev.of_node, "offset", &ctx->offset))
-		return -EINVAL;
+		if (of_property_read_u32(pdev->dev.of_node, "reg", &ctx->offset))
+			return -EINVAL;
 
 	value_err = of_property_read_u32(pdev->dev.of_node, "value", &ctx->value);
 	mask_err = of_property_read_u32(pdev->dev.of_node, "mask", &ctx->mask);