ARM: tegra: pinctrl: remove vddio

This field isn't used anywhere, so remove it. Note that PIN() macros are
left unchanged for now, to avoid many diffs to them; later commits will
completely rewrite them just one time.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>