ARM64: dts: meson-gxbb: Add USB Hub GPIO hog

The ODroid-C2 on-board USB Hub needs to to have it's reset signal set to
high level in order to be enumerated by the USB Host Controller.

But this management must be part of the currently in-development Generic
Power Sequence patch that will allow a USB Controller driver to start and stop
a power sequence associated to the USB Bus.

In the meantime, a simple USB Hog will work to enable the USB Hub.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>