cmd/dist,internal/platform: enable openbsd/ppc64 port

Updates #56001

Change-Id: I16440114ecf661e9fc17d304ab3b16bc97ef82f8
Reviewed-on: https://go-review.googlesource.com/c/go/+/517935
Run-TryBot: Joel Sing <[email protected]>
Reviewed-by: Paul Murphy <[email protected]>
Reviewed-by: Ian Lance Taylor <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>
Reviewed-by: Carlos Amedee <[email protected]>

Author: 4a6f656c

src/cmd/dist/build.go

@@ -1747,7 +1747,6 @@ var cgoEnabled = map[string]bool{
 var broken = map[string]bool{
 	"linux/sparc64":   true, // An incomplete port. See CL 132155.
 	"openbsd/mips64":  true, // Broken: go.dev/issue/58110.
-	"openbsd/ppc64":   true, // An incomplete port: go.dev/issue/56001.
 	"openbsd/riscv64": true, // An incomplete port: go.dev/issue/55999.
 }