Switch the creation of the combiner devices to the new-style
"embedded in state struct" approach, so we can easily refer
to the object elsewhere during realize.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220404154658.565020-18-peter.maydell@linaro.org