std: Add elf.EM, coff.MachineType to Target.CPU.Arch conversions
target.Arch already supports finding the correct encoding for either
target, so being able to do the inverse has use cases for when parsing
files of an unknown target (i.e. for zar).
9bb19a090eTom Maenan Read Cutting committed on 3/15/2022, 5:48:42 PM· committed by Andrew Kelleyparentc64279b