Debian: Fix /run/lock code

It looks like I messed this up (for Debian, but not Ubuntu) in my
various changes.  It is not necessary to do this before the chroot in
the normal install path, as it was done earlier.  But it is something
that should be done before the chroot in the rescue path.  I've now
made Debian match Ubuntu.

Fixes #141
Reported-by: Colm <colm@tuatha.org>
Signed-off-by: Richard Laager <rlaager@wiktel.com>

docs/Getting Started/Debian/Debian Buster Root on ZFS.rst

@@ -610,8 +610,6 @@ Step 4: System Configuration
      mount --rbind /dev  /mnt/dev
      mount --rbind /proc /mnt/proc
      mount --rbind /sys  /mnt/sys
-     mount -t tmpfs tmpfs /mnt/run
-     mkdir /mnt/run/lock
      chroot /mnt /usr/bin/env DISK=$DISK bash --login
 
    **Note:** This is using ``--rbind``, not ``--bind``.
@@ -1073,6 +1071,8 @@ If needed, you can chroot into your installed environment::
   mount --rbind /dev  /mnt/dev
   mount --rbind /proc /mnt/proc
   mount --rbind /sys  /mnt/sys
+  mount -t tmpfs tmpfs /mnt/run
+  mkdir /mnt/run/lock
   chroot /mnt /bin/bash --login
   mount /boot
   mount -a