Add nodes for the onboard USB hub on trogdor devices. Remove the
'always-on' property from the hub regulator, since the regulator
is now managed by the onboard_usb_hub driver.

For anyone using trogdor-based devices on Linux, it should be
noted that this requires "CONFIG_USB_ONBOARD_HUB=y".
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20220722093238.v24.1.I7a1a6448d50bdd38e6082204a9818c59cc7a9bfd@changeid