dtc has new checks for I2C buses. Fix the warnings in unit-addresses.

arch/arm/boot/dts/socfpga_cyclone5_de0_sockit.dtb: Warning (i2c_bus_reg): /soc/i2c@ffc04000/adxl345@0: I2C bus unit address format error, expected "53"
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>