pinctrl: imx: fix memory leak

Each time set_state is called, a new piece memory will
be allocated for pin_data, but not freed, this will
incur memory leak.

When error, the devm API could not free memory automatically.
So need call devm_kfree when error.

Issue reported by Coverity

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Stefan Agner <stefan.agner@toradex.com>
Cc: Stefano Babic <sbabic@denx.de>

drivers/pinctrl/nxp/pinctrl-imx.c

@@ -53,6 +53,7 @@ static int imx_pinctrl_set_state(struct udevice *dev, struct udevice *config)
 	if (fdtdec_get_int_array(gd->fdt_blob, node, "fsl,pins",
 				 pin_data, size >> 2)) {
 		dev_err(dev, "Error reading pin data.\n");
+		devm_kfree(dev, pin_data);
 		return -EINVAL;
 	}
 
@@ -78,6 +79,7 @@ static int imx_pinctrl_set_state(struct udevice *dev, struct udevice *config)
 
 		if ((mux_reg == -1) || (conf_reg == -1)) {
 			dev_err(dev, "Error mux_reg or conf_reg\n");
+			devm_kfree(dev, pin_data);
 			return -EINVAL;
 		}
 
@@ -166,6 +168,8 @@ static int imx_pinctrl_set_state(struct udevice *dev, struct udevice *config)
 		}
 	}
 
+	devm_kfree(dev, pin_data);
+
 	return 0;
 }