arm64: dts: imx8ulp: address build warning

Fix warnings such as:
 Warning (simple_bus_reg): /soc@0/gpio@2e200000: simple-bus unit address
 format error, expected "2e200080"

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>