i2c: designware: assert reset when error happen at ->probe()

The commit c62ebb3d5f0d ("i2c: designware: Add support for an interface clock")
introduced an optional clock while missed correct error handling.
assert reset line back if error happen at ->probe().

Fixes: c62ebb3d5f0d ("i2c: designware: Add support for an interface clock")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index ddfb818..4624ef8 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -346,8 +346,10 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
 
 	/* Optional interface clock */
 	dev->pclk = devm_clk_get_optional(&pdev->dev, "pclk");
-	if (IS_ERR(dev->pclk))
-		return PTR_ERR(dev->pclk);
+	if (IS_ERR(dev->pclk)) {
+		ret = PTR_ERR(dev->pclk);
+		goto exit_reset;
+	}
 
 	dev->clk = devm_clk_get(&pdev->dev, NULL);
 	if (!i2c_dw_prepare_clk(dev, true)) {