soc: mediatek: pm_domains: Make bus protection generic

Bus protection is not exclusively done by calling the infracfg misc driver.
Make the calls for setting and clearing the bus protection generic so
that we can use other blocks for it as well.

Signed-off-by: Matthias Brugger <mbrugger@suse.com>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Link: https://lore.kernel.org/r/20201030113622.201188-6-enric.balletbo@collabora.com


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