spi: rspi: Use NULL as the clock ID

There's only one RSPI/QSPI clock, so we can use NULL as the clock ID
Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Signed-off-by: Mark Brown <broonie@linaro.org>

drivers/spi/spi-rspi.c

@@ -1004,7 +1004,6 @@ static int rspi_probe(struct platform_device *pdev)
 	struct spi_master *master;
 	struct rspi_data *rspi;
 	int ret;
-	char clk_name[16];
 	const struct rspi_plat_data *rspi_pd = dev_get_platdata(&pdev->dev);
 	const struct spi_ops *ops;
 	const struct platform_device_id *id_entry = pdev->id_entry;
@@ -1034,8 +1033,7 @@ static int rspi_probe(struct platform_device *pdev)
 		goto error1;
 	}
 
-	snprintf(clk_name, sizeof(clk_name), "%s%d", id_entry->name, pdev->id);
-	rspi->clk = devm_clk_get(&pdev->dev, clk_name);
+	rspi->clk = devm_clk_get(&pdev->dev, NULL);
 	if (IS_ERR(rspi->clk)) {
 		dev_err(&pdev->dev, "cannot get clock\n");
 		ret = PTR_ERR(rspi->clk);