ARM: dts: imx7ulp: Fix usb-phy unit address format

The following warning is seen when building with W=1:

arch/arm/boot/dts/imx7ulp.dtsi:189.31-195.5: Warning (simple_bus_reg): /bus@40000000/usb-phy@0x40350000: simple-bus unit address format error, expected "40350000"

Fix it as suggested by removing the extra "0x" notation.

Fixes: 5b7bd456

 ("ARM: dts: imx7ulp: add imx7ulp USBOTG1 support")
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>