regulator: qcom-rpmh: Add stylistic breaks in the default cases

No functional change here but it can make the code more readable to
have breaks in the "default" case even though it's the last case.
Let's add them.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: David Collins <collinsd@codeaurora.org>
Signed-off-by: Mark Brown <broonie@kernel.org>