Add the power domains names to the power domain struct so we
have meaningful name for every power domain. This also removes the
following debugfs error message.

  [    2.242068] debugfs: Directory 'power-domain' with parent 'pm_genpd' already present!
  [    2.249949] debugfs: Directory 'power-domain' with parent 'pm_genpd' already present!
  [    2.257784] debugfs: Directory 'power-domain' with parent 'pm_genpd' already present!
  ...

Fixes: 59b644b0 ("soc: mediatek: Add MediaTek SCPSYS power domains")
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Reviewed-by: Hsin-Yi Wang <hsinyi@chromium.org>
Link: https://lore.kernel.org/r/20210225175000.824661-1-enric.balletbo@collabora.comSigned-off-by: Matthias Brugger <matthias.bgg@gmail.com>