pinctrl: rip out the direct pinconf API

From the inception ot the pin config API there has been the
possibility to get a handle at a pin directly and configure
its electrical characteristics. For this reason we had:

int pin_config_get(const char *dev_name, const char *name,
               unsigned long *config);
int pin_config_set(const char *dev_name, const char *name,
               unsigned long config);
int pin_config_group_get(const char *dev_name,
               const char *pin_group,
               unsigned long *config);
int pin_config_group_set(const char *dev_name,
               const char *pin_group,
               unsigned long config);

After the introduction of the pin control states that will
control pins associated with devices, and its subsequent
introduction to the device core, as well as the
introduction of pin control hogs that can set up states on
boot and optionally also at sleep, this direct pin control
API is a thing of the past.

As could be expected, it has zero in-kernel users.
Let's delete this API and make our world simpler.

Reported-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/Documentation/pinctrl.txt b/Documentation/pinctrl.txt
index 3ee2475..c5948c7 100644
--- a/Documentation/pinctrl.txt
+++ b/Documentation/pinctrl.txt
@@ -203,15 +203,8 @@
 stable value when nothing is driving the rail it is connected to, or when it's
 unconnected.
 
-Pin configuration can be programmed either using the explicit APIs described
-immediately below, or by adding configuration entries into the mapping table;
-see section "Board/machine configuration" below.
-
-For example, a platform may do the following to pull up a pin to VDD:
-
-#include <linux/pinctrl/consumer.h>
-
-ret = pin_config_set("foo-dev", "FOO_GPIO_PIN", PLATFORM_X_PULL_UP);
+Pin configuration can be programmed by adding configuration entries into the
+mapping table; see section "Board/machine configuration" below.
 
 The format and meaning of the configuration parameter, PLATFORM_X_PULL_UP
 above, is entirely defined by the pin controller driver.