for the brevity renaming direction_gpios to dir_gpios since STEP/DIR
interface is quite an established term in context of stepper controllers.
Signed-off-by: Jilay Pandya <jilay.pandya@outlook.com>
Adds a step direction binding that can be used with any stepper that
implements said control interface to cut down on boilerplate code.
Signed-off-by: Fabian Blatz <fabianblatz@gmail.com>