re PR go/65404 (cgo tool on powerpc-linux-gnu maybe incomplete)

	PR go/65404
go/build: cgo works on linux/pcc.

From-SVN: r221396

libgo/go/go/build/build.go

@@ -268,6 +268,7 @@ var cgoEnabled = map[string]bool{
 	"linux/alpha":     true,
 	"linux/amd64":     true,
 	"linux/arm":       true,
+	"linux/ppc":       true,
 	"linux/ppc64":     true,
 	"linux/ppc64le":   true,
 	"linux/s390":      true,