soc: mediatek: pm-domains: Add a meaningful power domain name

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.com


Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>