Bump runc to d5b4a3e

This fixes a race condition in runc/systemd at container creation time
opencontainers/runc#1683

Signed-off-by: vikaschoudhary16 <vichoudh@redhat.com>

vendor/github.com/containerd/console/tc_linux.go

@@ -0,0 +1,37 @@
+package console
+
+import (
+	"fmt"
+	"os"
+	"unsafe"
+
+	"golang.org/x/sys/unix"
+)
+
+const (
+	cmdTcGet = unix.TCGETS
+	cmdTcSet = unix.TCSETS
+)
+
+func ioctl(fd, flag, data uintptr) error {
+	if _, _, err := unix.Syscall(unix.SYS_IOCTL, fd, flag, data); err != 0 {
+		return err
+	}
+	return nil
+}
+
+// unlockpt unlocks the slave pseudoterminal device corresponding to the master pseudoterminal referred to by f.
+// unlockpt should be called before opening the slave side of a pty.
+func unlockpt(f *os.File) error {
+	var u int32
+	return ioctl(f.Fd(), unix.TIOCSPTLCK, uintptr(unsafe.Pointer(&u)))
+}
+
+// ptsname retrieves the name of the first available pts for the given master.
+func ptsname(f *os.File) (string, error) {
+	n, err := unix.IoctlGetInt(int(f.Fd()), unix.TIOCGPTN)
+	if err != nil {
+		return "", err
+	}
+	return fmt.Sprintf("/dev/pts/%d", n), nil
+}