To simplify the device specific dts, reuse the mt7621 default XHCI voltage regulators by adding the corresponding GPIO pin and polarity properties. Signed-off-by: Shiji Yang <yangshiji66@outlook.com> Link: https://github.com/openwrt/openwrt/pull/18886 Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>