pinctrl: remove bindings for pinconf options needing more thought

Some options currently take arguments in unspecified driver-specific units.
As pointed out by Stephen Warren, driver specific values should not be part
of generic devicetree bindings describing the hardware.

Therefore remove the critical bindings again, before they become part of
an official release.

Signed-off-by: Heiko Stuebner <[e-mail]>
Reviewed-by: James Hogan <[e-mail]>
Signed-off-by: Linus Walleij <[e-mail]>

Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt

···
 drive-strength		- sink or source at most X mA
 input-schmitt-enable	- enable schmitt-trigger mode
 input-schmitt-disable	- disable schmitt-trigger mode
-input-schmitt		- run in schmitt-trigger mode with hysteresis X
 input-debounce		- debounce mode with debound time X
-power-source		- select power source X
-slew-rate		- use slew-rate X
 low-power-enable	- enable low power mode
 low-power-disable	- disable low power mode
 output-low		- set the pin to output mode with low level
···
 
 - drive-strength takes as argument the target strength in mA.
 
-- input-schmitt takes as argument the adjustable hysteresis in a
-  driver-specific format
-
 - input-debounce takes the debounce time in usec as argument
   or 0 to disable debouncing
-
-- power-source argument is the custom value describing the source to select
-
-- slew-rate takes as argument the target rate in a driver-specific format
 
 All parameters not listed here, do not take an argument.
 

drivers/pinctrl/pinconf-generic.c

···
 	{ "drive-strength", PIN_CONFIG_DRIVE_STRENGTH, 0 },
 	{ "input-schmitt-enable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 1 },
 	{ "input-schmitt-disable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 0 },
-	{ "input-schmitt", PIN_CONFIG_INPUT_SCHMITT, 0 },
 	{ "input-debounce", PIN_CONFIG_INPUT_DEBOUNCE, 0 },
-	{ "power-source", PIN_CONFIG_POWER_SOURCE, 0 },
-	{ "slew-rate", PIN_CONFIG_SLEW_RATE, 0 },
 	{ "low-power-enable", PIN_CONFIG_LOW_POWER_MODE, 1 },
 	{ "low-power-disable", PIN_CONFIG_LOW_POWER_MODE, 0 },
 	{ "output-low", PIN_CONFIG_OUTPUT, 0, },