This change does two kinds of splits:
- Splits each target into a different file. Some targets are left in the
same files, such as riscv32/64 and x86/_64 as these tests and lists are
very similar.
- Splits up the very long 'note:' lines which contain a list of CPUs,
using `CHECK-SAME`. There was a note about this not being possible
before, but with `{{^}}`, this is now possible -- I have
verified that this does the right thing if a single CPU anywhere in the
list is left out.
These tests had become quite annoying to change when adding a CPU, and I
believe this change makes these easier to maintain, and should cut down
on conflicts in these files (or at least makes conflicts easier to
resolve).
I apologise in advance for downstream conflicts, but hopefully that's a
small amount of short term pain, in return for fewer conflicts in
future.
