clk: mediatek: reset: Return regmap's error code

device_node_to_regmap() can return different errors, and it's better
practice to pass them to callers.

Clean up the hardcoded -EINVAL and use PTR_ERR(regmap) instead.

Signed-off-by: Fei Shao <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Reviewed-by: AngeloGioacchino Del Regno <[e-mail]>
Signed-off-by: Stephen Boyd <[e-mail]>

drivers/clk/mediatek/reset.c

···
 	regmap = device_node_to_regmap(np);
 	if (IS_ERR(regmap)) {
 		pr_err("Cannot find regmap for %pOF: %pe\n", np, regmap);
-		return -EINVAL;
+		return PTR_ERR(regmap);
 	}
 
 	data = kzalloc(sizeof(*data), GFP_KERNEL);
···
 	regmap = device_node_to_regmap(np);
 	if (IS_ERR(regmap)) {
 		dev_err(dev, "Cannot find regmap %pe\n", regmap);
-		return -EINVAL;
+		return PTR_ERR(regmap);
 	}
 
 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);