i386: 0.960
graphic: 0.800
ppc: 0.730
semantic: 0.660
assembly: 0.644
device: 0.602
architecture: 0.598
kernel: 0.573
risc-v: 0.563
x86: 0.523
files: 0.510
socket: 0.477
network: 0.443
mistranslation: 0.426
vnc: 0.420
register: 0.388
performance: 0.371
VMM: 0.362
TCG: 0.353
debug: 0.329
permissions: 0.328
boot: 0.302
hypervisor: 0.265
virtual: 0.248
arm: 0.238
peripherals: 0.218
KVM: 0.198
user-level: 0.179
PID: 0.113

Avoid defining custom machine-definition macros for each new machine type
Additional information:
There are already some semi-generic implementations of this macro, such as [`DEFINE_PC_VER_MACHINE()`](https://gitlab.com/qemu-project/qemu/-/blob/aa3a285b5bc56a4208b3b57d4a55291e9c260107/include/hw/i386/pc.h#L326), which is used for the 'q35', 'pc' and 'isapc' machine types. 

There does appear to be some deviation from the template macro in some cases. We would have to enumerate what the nature of these deviations is, why only some machine types need them, and how they would fit into the proposed generic macro. Still, if we could have a generic macro that simplifies 80% of machine types' version definitions, then that seems like a win.