Any and all ISAs I may have interest in running FENIX on. Both the shorthand
to be used in `arch` folders and the full name are given.

i386 Intel i386 and derivatives; IA-32
amd64 64-bit extensions to IA-32; AKA x86_64
aarch64 64-bit ARM processors for stuff like the RPi and Pinebook
ppc64 Power ISA (specifically Power ISA v.3.0/POWER9)
riscv RISC-V alà the Beagle-V