cmd/dist: disable cgo for darwin/386

Fixes #31751

Change-Id: Id002f14557a34accc3597cb1b9a42e838a027da4
Reviewed-on: https://go-review.googlesource.com/c/go/+/174497Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/cmd/dist/build.go

@@ -1478,7 +1478,7 @@ func checkNotStale(goBinary string, targets ...string) {
 // by 'go tool dist list'.
 var cgoEnabled = map[string]bool{
 	"aix/ppc64":       true,
-	"darwin/386":      true,
+	"darwin/386":      false, // Issue 31751
 	"darwin/amd64":    true,
 	"darwin/arm":      true,
 	"darwin/arm64":    true,