i2c: i2c-gpio: fix name issue with multiple i2c gpio nodes

When having multiple i2c-gpio nodes, the name for each is same.
So add the patch to fix it.

The adap->name printing information was added by myself

without this patch the log information is as following
---<8---
adap->name = i2c-gpio-1
i2c-gpio i2c.2: using pins 30 (SDA) and 31 (SCL)
adap->name = i2c-gpio-1
i2c-gpio i2c.3: using pins 64 (SDA) and 65 (SCL)
--->8---

with this patch, the log information is as following
---<8---
adap->name = i2c.2
i2c-gpio i2c.2: using pins 30 (SDA) and 31 (SCL)
adap->name = i2c.3
i2c-gpio i2c.3: using pins 64 (SDA) and 65 (SCL)
--->8---
Signed-off-by: Bo Shen <voice.shen@atmel.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>

[wsa: minor fixes to the commit mesage]
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>

drivers/i2c/busses/i2c-gpio.c

@@ -184,7 +184,11 @@ static int __devinit i2c_gpio_probe(struct platform_device *pdev)
 	bit_data->data = pdata;
 
 	adap->owner = THIS_MODULE;
-	snprintf(adap->name, sizeof(adap->name), "i2c-gpio%d", pdev->id);
+	if (pdev->dev.of_node)
+		strlcpy(adap->name, dev_name(&pdev->dev), sizeof(adap->name));
+	else
+		snprintf(adap->name, sizeof(adap->name), "i2c-gpio%d", pdev->id);
+
 	adap->algo_data = bit_data;
 	adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
 	adap->dev.parent = &pdev->dev;