device-qcom-rbx: new aport

Caseyrequested to merge
casey/qcom-rbx into master

Add a generic device target which can boot on the Qualcomm rb3/5 and RB3 Gen 2 boards with EFI. The boards are expected to have U-Boot flashed as per the U-Boot documentation.

This port will support ongoing work at Linaro to enable and maintain upstream distro support for Qualcomm platforms and is expected to serve as a reference image.

Merge request reports