Dedupe compatible_sled_cpu_families across {Instance,Vmm}CpuPlatform - #11697

control: job assigned to worker 01M6HYQ8KJMPE9WEQYCE634QJB [factory aws, i-028ef517f0b6222d5] (queued for 52 s)
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task: starting task 0: "setup"
task: process exited: duration 4144 ms, exit code 0
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task: starting task 1: "rust-toolchain"
task: process exited: duration 18189 ms, exit code 0
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task: starting task 2: "authentication"
task: process exited: duration 20 ms, exit code 0
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task: starting task 3: "clone repository"
task: process exited: duration 17988 ms, exit code 0
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task: starting task 4: "build"
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| a out/probe.tar.gz 3037K
| a out/propolis-server.tar.gz 37167K
| a out/pumpkind-gz.tar 26647K
| a out/switch-softnpu.tar.gz 334636K
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| real     1:06.633511077
| user     1:04.373952633
| sys         3.694938553
| trap        0.005389768
| tflt        0.000000000
| dflt        0.000000000
| kflt        0.000000000
| lock        0.000000000
| slp      1:04.340021473
| lat         0.848068038
| stop        0.000224828
task: process exited: duration 1017013 ms, exit code 0
|W| found 1 output files
|W| uploading: /work/package.tar.gz (1877277770 bytes)
|W| uploaded: /work/package.tar.gz