Merge tag 'arm-soc/for-4.20/devicetree-arm64' of https://github.com/Broadcom/stblinux...

This pull request contains Broadcom ARM64-based SoCs Device Tree changes
for 4.20, please pull the following:

- Stefan provides a reference to the Compute Module IO Board V3 such
  that we can reference the arm counterpart and still build it for arm64

- Rob fixes I2C and SPI bus warnings which are going to show up with his
  update to DTC scheduled for 4.20

* tag 'arm-soc/for-4.20/devicetree-arm64' of https://github.com/Broadcom/stblinux:
  arm64: dts: broadcom: Fix I2C and SPI bus warnings
  arm64: dts: broadcom: Add reference to Compute Module IO Board V3

Signed-off-by: Olof Johansson <olof@lixom.net>