x/build: no trybot for compile-only linux/arm64

[bradfitz]

I just submitted two arm64 CLs which don't even compile, but pass trybots:

https://go-review.googlesource.com/c/go/+/61570
https://go-review.googlesource.com/c/go/+/61550

I don't know why Trybots didn't catch this. I guess we no longer have linux/arm64 trybots.

/cc @zhangfannie @ianlancetaylor

[gopherbot]

Change https://golang.org/cl/77590 mentions this issue: crypto, internal/cpu: add noescape annotations, fix arm64 build

[bradfitz]

Actually, there is trybot coverage:

        addMiscCompile("", "^(linux-arm64|nacl-arm|solaris-amd64|darwin-386)$") // 4 ports                                                                
        addMiscCompile("-mips", "^linux-mips")                                  // 4                                                                      
        addMiscCompile("-ppc", "^linux-ppc64")                                  // 2                                                                      
        addMiscCompile("-plan9", "^plan9-")                                     // 3                                                                      
        addMiscCompile("-freebsd", "^freebsd-")                                 // 3                                                                      
        addMiscCompile("-netbsd", "^netbsd-")                                   // 3                                                                      
        addMiscCompile("-openbsd", "^openbsd-")                                 // 3                                                                      

These CLs were atop the necessary https://go.googlesource.com/go/+/ee50d79e8b1e14f1c867883be56dd821551cc7e4 but when I submitted, it cherry-picked to master.

Closing in favor of #22123 and #12482.