USB VBUS regulators are now specified with the vbus-supply property
instead of nvidia,vbus-gpio, so remove the obsolete properties.
The equivalent vbus-supply properties were already added in patch
"ARM: tegra: update device trees for USB binding rework".
Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com> Acked-by: Stephen Warren <swarren@nvidia.com> Reviewed-by: Stephen Warren <swarren@nvidia.com> Tested-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Felipe Balbi <balbi@ti.com>