gpio: name PCA953x gpio chips after device name

Instead of using the name directly from the I2C client
to name the gpio_chip, use dev_name() on the client->dev,
so we get the sometimes more unique device name, as I2C has
a mechanism for naming its devices explicitly in e.g.
board data.

This is a prerequisite for being able to reference
uniquely any I2C GPIO expander defined in a board file
when setting up GPIO descriptor tables.
Reviewed-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/gpio/gpio-pca953x.c

@@ -449,7 +449,7 @@ static void pca953x_setup_gpio(struct pca953x_chip *chip, int gpios)
 
 	gc->base = chip->gpio_start;
 	gc->ngpio = gpios;
-	gc->label = chip->client->name;
+	gc->label = dev_name(&chip->client->dev);
 	gc->parent = &chip->client->dev;
 	gc->owner = THIS_MODULE;
 	gc->names = chip->names;