arm64: dts: exynos: gs101-oriole: add placeholder regulators for USB phy

arm64: dts: exynos: gs101-oriole: add placeholder regulators for USB phy

The USB phy requires various power supplies to work.

While we don't have a PMIC driver yet, the supplies should still be
added to the DT.

Add some placeholders, which will be replaced with the real ones once
we implement PMIC.

Signed-off-by: André Draszik <andre.draszik@linaro.org>
Link: https://lore.kernel.org/r/20240618-gs101-usb-regulators-in-dt-v3-1-6a749207052e@linaro.org
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>