PM: domains: Add the domain HW-managed mode to the summary

Now that genpd supports dynamically switching the control for an
attached device between hardware- and software-mode, let's add this
information to the genpd summary under managed by column in debugfs.

Suggested-by: Taniya Das <quic_tdas@quicinc.com>
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
Signed-off-by: Jagadeesh Kona <quic_jkona@quicinc.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Bjorn Andersson <andersson@kernel.org>
Reviewed-by: Dhruva Gole <d-gole@ti.com>
Reviewed-by: Taniya Das <quic_tdas@quicinc.com>
Link: https://lore.kernel.org/r/20240624044809.17751-3-quic_jkona@quicinc.com


Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>