phy: phy-mtk-dp: Fix an error code in probe()

Negative -EINVAL was intended instead of positive EINVAL.

Fixes: 6a23afa ("phy: phy-mtk-dp: Add driver for DP phy")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>
Link: https://lore.kernel.org/r/3c699e00-2883-40d9-92c3-0da1dc38fdd4@moroto.mountain
Signed-off-by: Vinod Koul <vkoul@kernel.org>

Author: Dan Carpenter

drivers/phy/mediatek/phy-mtk-dp.c

@@ -169,7 +169,7 @@ static int mtk_dp_phy_probe(struct platform_device *pdev)
 
 	regs = *(struct regmap **)dev->platform_data;
 	if (!regs)
-		return dev_err_probe(dev, EINVAL,
+		return dev_err_probe(dev, -EINVAL,
 				     "No data passed, requires struct regmap**\n");
 
 	dp_phy = devm_kzalloc(dev, sizeof(*dp_phy), GFP_KERNEL);