regulator: pwm-regulator: Fix 'unused-variable' warning

drivers/regulator/pwm-regulator.c:
  In function 'pwm_regulator_init_continuous':
drivers/regulator/pwm-regulator.c:202:22:
  warning: unused variable 'np' [-Wunused-variable]
     struct device_node *np = pdev->dev.of_node;
              ^
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NLee Jones <lee.jones@linaro.org>
Signed-off-by: NMark Brown <broonie@kernel.org>

drivers/regulator/pwm-regulator.c

@@ -198,8 +198,6 @@ static int pwm_regulator_init_table(struct platform_device *pdev,
 static int pwm_regulator_init_continuous(struct platform_device *pdev,
 					 struct pwm_regulator_data *drvdata)
 {
-	struct device_node *np = pdev->dev.of_node;
-
 	pwm_regulator_desc.ops = &pwm_regulator_voltage_continuous_ops;
 	pwm_regulator_desc.continuous_voltage_range = true;