pinctrl: pinctrl-at91.c: Cleaning up if unsigned is less than zero

Remove checking if a unsigned is less than zero

This was found using a static code analysis program called cppcheck.

Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/pinctrl/pinctrl-at91.c b/drivers/pinctrl/pinctrl-at91.c
index bd57ab5..ec9744f 100644
--- a/drivers/pinctrl/pinctrl-at91.c
+++ b/drivers/pinctrl/pinctrl-at91.c
@@ -924,7 +924,7 @@
 	/* Initialise function */
 	func->name = np->name;
 	func->ngroups = of_get_child_count(np);
-	if (func->ngroups <= 0) {
+	if (func->ngroups == 0) {
 		dev_err(info->dev, "no groups defined\n");
 		return -EINVAL;
 	}