Depending on the architecture, requirements for ACPI and UEFI can
be different; more specifically, while on x86 UEFI requires ACPI,
on aarch64 it's the other way around.
Enforce these requirements when validating the domain, and make
the error message more accurate by mentioning that they're not
necessarily applicable to all architectures.
Several aarch64 test cases had to be tweaked because they would
have failed the validation step otherwise.
Most qemuxml2xml tests expect that the input XML is unchanged after
parsing. This is unlike 99% of new qemu configs in the wild, which after
initial parsing end up with stable PCI device addresses. The xml2xml bit
doesn't currently hit that code path though, so most XML testing indeed
does not change.
Future patches will add that PCI address bits, which means most test cases
will have different output. So let's do away with the hardcoded same vs
different test split, and always track a separate output file. Tests can
still have same input and output, it just necessitates 2 separate XML files.