The only time that could happen where it would make sense is if we have a 32-bit dom0 introspecting a 64-bit domU. But that distinction doesn't make any difference in what ifdefs are triggered in the code. Cross-compiling LibVMI from x86 host to ARM doesn't really make much sense as the Xen headers themselves present on x86 would break the compilation. And this PR doesn't add file-mode support for the ARM layout as we don't have any heuristics to find a dtb in the memory dump of a linux PV domain.