ARM: SAMSUNG: Fix null pointer dereference in ADC driver

ARM: SAMSUNG: Fix null pointer dereference in ADC driver

Use struct adc_device instead of relying on client (which could be
NULL) when checking for SoC type.
Signed-off-by: Maurus Cuelenaere <mcuelenaere@gmail.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>

arch/arm/plat-samsung/adc.c

@@ -295,7 +295,7 @@ static irqreturn_t s3c_adc_irq(int irq, void *pw)
 	}
 
 exit:
-	if (platform_get_device_id(client->pdev)->driver_data == TYPE_S3C64XX) {
+	if (platform_get_device_id(adc->pdev)->driver_data == TYPE_S3C64XX) {
 		/* Clear ADC interrupt */
 		writel(0, adc->regs + S3C64XX_ADCCLRINT);
 	}