gpio: change member .dev to .parent

The name .dev in a struct is normally reserved for a struct device
that is let us say a superclass to the thing described by the struct.
struct gpio_chip stands out by confusingly using a struct device *dev
to point to the parent device (such as a platform_device) that
represents the hardware. As we want to give gpio_chip:s real devices,
this is not working. We need to rename this member to parent.

This was done by two coccinelle scripts, I guess it is possible to
combine them into one, but I don't know such stuff. They look like
this:

@@
struct gpio_chip *var;
@@
-var->dev
+var->parent

and:

@@
struct gpio_chip var;
@@
-var.dev
+var.parent

and:

@@
struct bgpio_chip *var;
@@
-var->gc.dev
+var->gc.parent

Plus a few instances of bgpio that I couldn't figure out how
to teach Coccinelle to rewrite.

This patch hits all over the place, but I *strongly* prefer this
solution to any piecemal approaches that just exercise patch
mechanics all over the place. It mainly hits drivers/gpio and
drivers/pinctrl which is my own backyard anyway.

Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Rafał Miłecki <zajec5@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Cc: Alek Du <alek.du@intel.com>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Acked-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/pinctrl/bcm/pinctrl-bcm2835.c b/drivers/pinctrl/bcm/pinctrl-bcm2835.c
index a1ea565..0bc1abc 100644
--- a/drivers/pinctrl/bcm/pinctrl-bcm2835.c
+++ b/drivers/pinctrl/bcm/pinctrl-bcm2835.c
@@ -337,7 +337,7 @@
 
 static int bcm2835_gpio_get(struct gpio_chip *chip, unsigned offset)
 {
-	struct bcm2835_pinctrl *pc = dev_get_drvdata(chip->dev);
+	struct bcm2835_pinctrl *pc = dev_get_drvdata(chip->parent);
 
 	return bcm2835_gpio_get_bit(pc, GPLEV0, offset);
 }
@@ -350,14 +350,14 @@
 
 static void bcm2835_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 {
-	struct bcm2835_pinctrl *pc = dev_get_drvdata(chip->dev);
+	struct bcm2835_pinctrl *pc = dev_get_drvdata(chip->parent);
 
 	bcm2835_gpio_set_bit(pc, value ? GPSET0 : GPCLR0, offset);
 }
 
 static int bcm2835_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
 {
-	struct bcm2835_pinctrl *pc = dev_get_drvdata(chip->dev);
+	struct bcm2835_pinctrl *pc = dev_get_drvdata(chip->parent);
 
 	return irq_linear_revmap(pc->irq_domain, offset);
 }
@@ -963,7 +963,7 @@
 		return PTR_ERR(pc->base);
 
 	pc->gpio_chip = bcm2835_gpio_chip;
-	pc->gpio_chip.dev = dev;
+	pc->gpio_chip.parent = dev;
 	pc->gpio_chip.of_node = np;
 
 	pc->irq_domain = irq_domain_add_linear(np, BCM2835_NUM_GPIOS,