pinctrl: ingenic: Fixup PIN_CONFIG_OUTPUT config

JZ4760 support was added in parallel of the previous patch so this one
slipped through. The first SoC to use the new register is the JZ4760 and
not the JZ4770, fix it here.

Fixes: 7009d046

 ("pinctrl: ingenic: Handle PIN_CONFIG_OUTPUT config")
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Link: https://lore.kernel.org/r/20191210164446.53912-1-paul@crapouillou.net
[Folded into OF dependency]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>