pinctrl: mark non-EXPERIMENTAL

With the finalization of the external driver API and the device
tree support, this subsystem is now mature and can be promoted to
non-experimental status.
Acked-by: NStephen Warren <swarren@wwwdotorg.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/Kconfig

@@ -4,7 +4,6 @@
 
 config PINCTRL
 	bool
-	depends on EXPERIMENTAL
 
 if PINCTRL