Version 8 of Arm architecture defined 64-bit execution state called AArch64. RedHat-based distributions (and GNU tools) use "aarch64" name for it, but Debian went (as Linux kernel) with "arm64" string. This introduced the same "schism" as happened with "x86_64" and "arm64" and has to be handled by Debian-related routines.

I propose the simplest solution for the problem, adding string substitution similar to what happens for x86_64 in relevant places. I've grepped the whole core for amd64, but if I missed anything or used wrong coding practice, I'll be more than happy to address any feedback.