Cannot build wuzz with go 1.18

[Michael Madden]

I cannot build wuzz with go 1.18:

$ go version
go version go1.18 darwin/amd64

$ sw_vers
ProductName:	macOS
ProductVersion:	12.3
BuildVersion:	21E230

$ go install github.com/asciimoo/wuzz@latest
# golang.org/x/sys/unix
go/pkg/mod/golang.org/x/sys@v0.0.0-20200602225109-6fdc65e7d980/unix/syscall_darwin.1_13.go:29:3: //go:linkname must refer to declared function or variable
go/pkg/mod/golang.org/x/sys@v0.0.0-20200602225109-6fdc65e7d980/unix/zsyscall_darwin_amd64.1_13.go:27:3: //go:linkname must refer to declared function or variable
go/pkg/mod/golang.org/x/sys@v0.0.0-20200602225109-6fdc65e7d980/unix/zsyscall_darwin_amd64.1_13.go:40:3: //go:linkname must refer to declared function or variable
go/pkg/mod/golang.org/x/sys@v0.0.0-20200602225109-6fdc65e7d980/unix/zsyscall_darwin_amd64.go:28:3: //go:linkname must refer to declared function or variable
go/pkg/mod/golang.org/x/sys@v0.0.0-20200602225109-6fdc65e7d980/unix/zsyscall_darwin_amd64.go:43:3: //go:linkname must refer to declared function or variable
go/pkg/mod/golang.org/x/sys@v0.0.0-20200602225109-6fdc65e7d980/unix/zsyscall_darwin_amd64.go:59:3: //go:linkname must refer to declared function or variable
go/pkg/mod/golang.org/x/sys@v0.0.0-20200602225109-6fdc65e7d980/unix/zsyscall_darwin_amd64.go:75:3: //go:linkname must refer to declared function or variable
go/pkg/mod/golang.org/x/sys@v0.0.0-20200602225109-6fdc65e7d980/unix/zsyscall_darwin_amd64.go:90:3: //go:linkname must refer to declared function or variable
go/pkg/mod/golang.org/x/sys@v0.0.0-20200602225109-6fdc65e7d980/unix/zsyscall_darwin_amd64.go:105:3: //go:linkname must refer to declared function or variable
go/pkg/mod/golang.org/x/sys@v0.0.0-20200602225109-6fdc65e7d980/unix/zsyscall_darwin_amd64.go:121:3: //go:linkname must refer to declared function or variable
go/pkg/mod/golang.org/x/sys@v0.0.0-20200602225109-6fdc65e7d980/unix/zsyscall_darwin_amd64.go:121:3: too many errors

[Michael Madden]

Here is a PR to fix the issue building with Go 1.18: #143