This breaks chromebook_coral and it is also not how things should work. If
a board needs to bind GPIOs as part of a pinctrl driver this can be done
during the bind step, if needed.

We cannot probe pinctrl devices when binding as a rule, since it cannot be
supported on some platforms.

The bind and probe steps are separate in U-Boot and they should remain
separate.

This reverts commit f9ec791b.

Signed-off-by: Simon Glass <sjg@chromium.org>