spi/s3c64xx: Take runtime PM reference even if DMA is not supported

We always need the device to be runtime PM enabled to use it so just skip
the DMA initialisation not the entire prepare when polling.
Signed-off-by: Mark Brown <broonie@linaro.org>

drivers/spi/spi-s3c64xx.c

@@ -429,9 +429,7 @@ static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
 	dma_cap_mask_t mask;
 	int ret;
 
-	if (is_polling(sdd))
-		return 0;
-
+	if (!is_polling(sdd)) {
 		dma_cap_zero(mask);
 		dma_cap_set(DMA_SLAVE, mask);
 
@@ -451,6 +449,7 @@ static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
 			ret = -EBUSY;
 			goto out_rx;
 		}
+	}
 
 	ret = pm_runtime_get_sync(&sdd->pdev->dev);
 	if (ret < 0) {