ARM: tegra: Select PINCTRL Kconfig variables

This causes the Tegra pinctrl driver to be built whenever core Tegra
support is enabled.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>