usb: dwc3: Remove impossible check for of_clk_get_parent_count() < 0

The check for < 0 is impossible now that
of_clk_get_parent_count() returns an unsigned int. Simplify the
code and update the types.
Acked-by: NFelipe Balbi <balbi@kernel.org>
Cc: <linux-usb@vger.kernel.org>
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>

drivers/usb/dwc3/dwc3-of-simple.c

@@ -42,6 +42,7 @@ static int dwc3_of_simple_probe(struct platform_device *pdev)
 	struct device		*dev = &pdev->dev;
 	struct device_node	*np = dev->of_node;
 
+	unsigned int		count;
 	int			ret;
 	int			i;
 
@@ -49,11 +50,11 @@ static int dwc3_of_simple_probe(struct platform_device *pdev)
 	if (!simple)
 		return -ENOMEM;
 
-	ret = of_clk_get_parent_count(np);
-	if (ret < 0)
-		return ret;
+	count = of_clk_get_parent_count(np);
+	if (!count)
+		return -ENOENT;
 
-	simple->num_clocks = ret;
+	simple->num_clocks = count;
 
 	simple->clks = devm_kcalloc(dev, simple->num_clocks,
 			sizeof(struct clk *), GFP_KERNEL);