arm64: dts: freescale: imx93-phyboard-nash: Add USB vbus regulators

arm64: dts: freescale: imx93-phyboard-nash: Add USB vbus regulators

Add USB vbus regulators to silence the following kernel warnings:

  usb_phy_generic usbphynop1: dummy supplies not allowed for exclusive requests (id=vbus)
  usb_phy_generic usbphynop2: dummy supplies not allowed for exclusive requests (id=vbus)

Because generic USB PHY driver requires exclusive vbus regulators since
commit 75fd6485ccce ("usb: phy: generic: Get the vbus supply").

Signed-off-by: Primoz Fiser <primoz.fiser@norik.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>