dtc: Revert unintentional submodule downgrade from commit c2cabb34220d63f9
Commit c2cabb34220d63f9 inadvertently downgraded the 'dtc' submodule,
undoing the increments added in earlier commits. Revert this,
returning the submodule state to where we should be.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Peter Maydell