spi: rspi: Use devm_kasprintf()

Use the devm_kasprintf() helper function instead of open coding
error-prone buffer handling and string formatting.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NMark Brown <broonie@linaro.org>

drivers/spi/spi-rspi.c

@@ -1046,12 +1046,11 @@ static int rspi_request_irq(struct device *dev, unsigned int irq,
 			    irq_handler_t handler, const char *suffix,
 			    void *dev_id)
 {
-	const char *base = dev_name(dev);
-	size_t len = strlen(base) + strlen(suffix) + 2;
-	char *name = devm_kzalloc(dev, len, GFP_KERNEL);
+	const char *name = devm_kasprintf(dev, GFP_KERNEL, "%s:%s",
+					  dev_name(dev), suffix);
 	if (!name)
 		return -ENOMEM;
-	snprintf(name, len, "%s:%s", base, suffix);
+
 	return devm_request_irq(dev, irq, handler, 0, name, dev_id);
 }