device tree compilation warnings.

[stolk]

The device tree compiler (dtc 1.6.1) gives the following warnings:

==================== build dtb =====================
/home/bram/src/bl808_linux/bl808_dts/hw808c.dts:51.21-56.5: Warning (simple_bus_reg): /soc/mm-clock: missing or empty reg/ranges property
/home/bram/src/bl808_linux/bl808_dts/hw808c.dts:58.12-62.5: Warning (simple_bus_reg): /soc/pmu: missing or empty reg/ranges property
/home/bram/src/bl808_linux/bl808_dts/hw808c.dts:24.36-28.6: Warning (interrupt_provider): /cpus/cpu@0/interrupt-controller: Missing #address-cells in interrupt provider
/home/bram/src/bl808_linux/bl808_dts/hw808c.dts:38.39-49.5: Warning (interrupt_provider): /soc/interrupt-controller@e0000000: Missing #address-cells in interrupt provider