Merge bug-1306824-add-processor-info-reader-for-aarch64 [f=1306824] [r=bjornt,adam-collard] [a=Benji York]
The 64-bit ARMv8 architechture has "aarm64" reported as its machine name, which
didn't match the ARM regex.
This branch adds a test that generated the error and a tweaked regex that
recognizes the machine name.