staging: iio: spear_adc: Remove redundant platform_set_drvdata()

Commit 0998d06310 (device-core: Ensure drvdata = NULL when no
driver is bound) removes the need to set driver data field to
NULL.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Stefan Roese <sr@denx.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/staging/iio/adc/spear_adc.c

@@ -407,7 +407,6 @@ static int spear_adc_remove(struct platform_device *pdev)
 	struct spear_adc_info *info = iio_priv(iodev);
 
 	iio_device_unregister(iodev);
-	platform_set_drvdata(pdev, NULL);
 	clk_disable_unprepare(info->clk);
 	clk_put(info->clk);
 	iounmap(info->adc_base_spear6xx);