Change cpuType default to null

[afbjorklund]

Avoid issues with converting null strings in a map value

Change order to alphabetical, to match the "limactl info"

---

Helps with:

• simplify FillDefault() using reflects #1069

• Add command to generate jsonschema for limayaml #2306

[afbjorklund]

Note: the -pdpe1gb is only true when running on a Darwin host, not on Linux (and looks a bit odd).

But I figured it is best to have details in the code, and avoid duplicating them here... Maybe remove it?

cpuType:
  # aarch64: "cortex-a72" # (or "host" when running on aarch64 host)
  # armv7l: "cortex-a7" # (or "host" when running on armv7l host)
  # riscv64: "rv64" # (or "host" when running on riscv64 host)
  # x86_64: "qemu64" # (or "host" when running on x86_64 host)

[AkihiroSuda]

Why remove these lines?

[afbjorklund]

There is a problem with the json, when it is trying to marshal "null" into a string value...

After changing CPUType to map[Arch]*string, it is a problem to express as jsonschema.

Also, it means that we don't have to carry the list of architectures in the "empty" yaml?

Made some similar changes to ssh.localPort and Rosetta omitempty, but will post separately

[afbjorklund]

 images: []
-cpuType:
-  aarch64: ""
-  armv7l: ""
-  riscv64: ""
-  x86_64: ""
-ssh:
-  localPort: 0

{
   "audio" : {},
   "caCerts" : {},
   "containerd" : {},
   "cpuType" : {
      "aarch64" : "",
      "armv7l" : "",
      "riscv64" : "",
      "x86_64" : ""
   },
   "firmware" : {},
   "hostResolver" : {},
   "images" : null,
   "rosetta" : {
      "binfmt" : null,
      "enabled" : null
   },
   "ssh" : {
      "localPort" : 0
   },
   "video" : {
      "vnc" : {}
   }
}

[afbjorklund]

Also the (text of the) lines are not removed, they are just translated into comments instead.

When uncommented, the default is reconstructed (could use "" or null for empty values)

 cpuType:
  aarch64: "cortex-a72" # (or "host" when running on aarch64 host)
  armv7l: "cortex-a7" # (or "host" when running on armv7l host)
  riscv64: "rv64" # (or "host" when running on riscv64 host)
  x86_64: "qemu64" # (or "host,-pdpe1gb" when running on x86_64 host)

[AkihiroSuda]

Thanks