Bump packages to new alpine w/ containerd v1.1.0-rc.2

Since we are building containerd v1.1.0 with go 1.10 (as it requires) to the
same for init and runc too for consistency. In the case of init it is actually
required since we use the containerd client library there.

The subreaper interfaces have been removed from containerd and replaced with a
similar interface in runc/libcontainer, update init to use that now.

Signed-off-by: Ian Campbell <ijc@docker.com>

pkg/init/cmd/service/runc.go

@@ -9,7 +9,7 @@ import (
 	"path/filepath"
 	"strconv"
 
-	"github.com/containerd/containerd/sys"
+	"github.com/opencontainers/runc/libcontainer/system"
 	log "github.com/sirupsen/logrus"
 )
 
@@ -49,7 +49,7 @@ func runcInit(rootPath, serviceType string) int {
 	}
 
 	// need to set ourselves as a child subreaper or we cannot wait for runc as reparents to init
-	if err := sys.SetSubreaper(1); err != nil {
+	if err := system.SetSubreaper(1); err != nil {
 		log.Fatalf("Cannot set as subreaper: %v", err)
 	}