Enable the autobuilder to function properly on Arm 64bit hardware (Aarch64)
More specifically we need to move the arm worker out of bringup and have it start executing the qemuarm64-ptest and qemuarm64-ltp targets. We need to switch ADKMACHINE to aarch64 for the esdk builds which is a current source of errors as SDK must equal build arch for esdk (can't avoid that due to technical constraints in the way it works).
This is now ready apart from the configuration to add it to a-full and a-quick. We need bug 13373 fixed before we can do that.
These are now being run on the autobuilder as part of standard a-full and a-quick builds.