pinctrl: ingenic: Add OTG VBUS pin for the JZ4770

Add pin mux configuration for the OTG VBUS pin of the JZ4770.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Link: https://lore.kernel.org/r/20191119155211.102527-2-paul@crapouillou.net


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>