gpio: pxa: remove set but not used variable 'gpio_offset'

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/gpio/gpio-pxa.c: In function "pxa_gpio_probe":
drivers/gpio/gpio-pxa.c:629:35: warning:
 variable "gpio_offset" set but not used [-Wunused-but-set-variable]
  int irq0 = 0, irq1 = 0, irq_mux, gpio_offset = 0;
                                   ^
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/gpio/gpio-pxa.c

@@ -626,7 +626,7 @@ static int pxa_gpio_probe(struct platform_device *pdev)
 	struct pxa_gpio_platform_data *info;
 	void __iomem *gpio_reg_base;
 	int gpio, ret;
-	int irq0 = 0, irq1 = 0, irq_mux, gpio_offset = 0;
+	int irq0 = 0, irq1 = 0, irq_mux;
 
 	pchip = devm_kzalloc(&pdev->dev, sizeof(*pchip), GFP_KERNEL);
 	if (!pchip)
@@ -672,9 +672,6 @@ static int pxa_gpio_probe(struct platform_device *pdev)
 	if (!gpio_reg_base)
 		return -EINVAL;
 
-	if (irq0 > 0)
-		gpio_offset = 2;
-
 	clk = clk_get(&pdev->dev, NULL);
 	if (IS_ERR(clk)) {
 		dev_err(&pdev->dev, "Error %ld to get gpio clock\n",