pinctrl: st: Fix Sparse error

This change fixes below sparse error,
drivers/pinctrl/pinctrl-st.c:1515:31: error: incompatible types for operation (>)
drivers/pinctrl/pinctrl-st.c:1515:31:    left side has type void [noderef] <asn:2>*irqmux_base
drivers/pinctrl/pinctrl-st.c:1515:31:    right side has type int

Cc: Maxime Coquelin <maxime.coquelin@st.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
CC: Linus Walleij <linus.walleij@linaro.org>
Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Pramod Gurav <pramod.gurav@smartplayin.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/pinctrl-st.c

@@ -1512,7 +1512,7 @@ static int st_gpiolib_register_bank(struct st_pinctrl *info,
 					     gpio_irq, st_gpio_irq_handler);
 	}
 
-	if (info->irqmux_base > 0 || gpio_irq > 0) {
+	if (info->irqmux_base || gpio_irq > 0) {
 		err = gpiochip_irqchip_add(&bank->gpio_chip, &st_gpio_irqchip,
 					   0, handle_simple_irq,
 					   IRQ_TYPE_LEVEL_LOW);