ASoC: sgtl5000: Use the preferred form for passing a size of a struct

According to Documentation/CodingStyle - Chapter 14:

"The preferred form for passing a size of a struct is the following:

	p = kmalloc(sizeof(*p), ...);

The alternative form where struct name is spelled out hurts readability and
introduces an opportunity for a bug when the pointer variable type is changed
but the corresponding sizeof that is passed to a memory allocator is not."

So do it as recommeded.
Signed-off-by: NFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: NMark Brown <broonie@kernel.org>

sound/soc/codecs/sgtl5000.c

@@ -1439,8 +1439,7 @@ static int sgtl5000_i2c_probe(struct i2c_client *client,
 	struct device_node *np = client->dev.of_node;
 	u32 value;
 
-	sgtl5000 = devm_kzalloc(&client->dev, sizeof(struct sgtl5000_priv),
-								GFP_KERNEL);
+	sgtl5000 = devm_kzalloc(&client->dev, sizeof(*sgtl5000), GFP_KERNEL);
 	if (!sgtl5000)
 		return -ENOMEM;