pmdomain: rockchip: forward rockchip_do_pmu_set_power_domain errors

Currently rockchip_do_pmu_set_power_domain prints a warning if there
have been errors turning on the power domain, but it does not return
any errors and rockchip_pd_power() tries to continue setting up the
QOS registers. This usually results in accessing unpowered registers,
which triggers an SError and a full system hang.

This improves the error handling by forwarding the error to avoid
kernel panics.

Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Adrian Larumbe <adrian.larumbe@collabora.com> # On Rock 5B
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Link: https://lore.kernel.org/r/20250220-rk3588-gpu-pwr-domain-regulator-v6-3-a4f9c24e5b81@kernel.org


[Ulf: Fixed conflict when applying]
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>