pinctrl: actions: fix unsigned less than zero comparison

The check to see if platform_get_irq failed is performed on the
unsigned value of pctrl->irq[i] and the check is never true because
an unsigned cannot be less than zero.  Fix this by assinging the
signed int ret to the return of platform_get_irq and checking ret
instead.

Detected by CoverityScan, CID#1470247 ("Unsigned comparison against 0")

Fixes: 6c5d0736 ("pinctrl: actions: Add interrupt support for OWL S900 SoC")
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Acked-by: NManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/actions/pinctrl-owl.c

@@ -1026,11 +1026,10 @@ int owl_pinctrl_probe(struct platform_device *pdev,
 	}
 
 	for (i = 0; i < pctrl->num_irq ; i++) {
-		pctrl->irq[i] = platform_get_irq(pdev, i);
-		if (pctrl->irq[i] < 0) {
-			ret = pctrl->irq[i];
+		ret = platform_get_irq(pdev, i);
+		if (ret < 0)
 			goto err_exit;
-		}
+		pctrl->irq[i] = ret;
 	}
 
 	ret = owl_gpio_init(pctrl);