gpiolib: of: remove [devm_]gpiod_get_from_of_node() APIs

Now that everyone is using [devm_]fwnode_gpiod_get[_index]() APIs,
remove OF-specific [devm_]gpiod_get_from_of_node().

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>