pinctrl: imx: do not implicitly set pin regs to -1

Commit 3dac1918a491 ("pinctrl: imx: detect uninitialized pins") needs
the values in struct imx_pin_reg to be -1. This has been done in a
rather unorthodox way by setting the memory to 0xff using memset...
Use a proper for loop to initialize the whole array with -1.

Signed-off-by: Stefan Agner <stefan@agner.ch>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/freescale/pinctrl-imx.c

@@ -645,7 +645,7 @@ int imx_pinctrl_probe(struct platform_device *pdev,
 {
 	struct imx_pinctrl *ipctl;
 	struct resource *res;
-	int ret;
+	int ret, i;
 
 	if (!info || !info->pins || !info->npins) {
 		dev_err(&pdev->dev, "wrong pinctrl info\n");
@@ -662,7 +662,11 @@ int imx_pinctrl_probe(struct platform_device *pdev,
 				      info->npins, GFP_KERNEL);
 	if (!info->pin_regs)
 		return -ENOMEM;
-	memset(info->pin_regs, 0xff, sizeof(*info->pin_regs) * info->npins);
+
+	for (i = 0; i < info->npins; i++) {
+		info->pin_regs[i].mux_reg = -1;
+		info->pin_regs[i].conf_reg = -1;
+	}
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	ipctl->base = devm_ioremap_resource(&pdev->dev, res);