Drop the hub_5v regulator which controls the HUB Reset line with GPIOH_4 which
is already controlled by a GPIO HOG.

Until we can properly describe how to control USB HUBs reset lines, keeping
the GPIO HOG is an acceptable solution we use on multiple boards.
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Link: https://lore.kernel.org/r/20210607065435.577334-8-narmstrong@baylibre.com