soc: mediatek: pm-domains: Add domain_supply cap for mfg_async PD

The mfg_async power domain in mt8173 is used to power up imgtec
gpu. This domain requires the da9211 regulator to be enabled before
the power domain can be enabled successfully.

Signed-off-by: Bilal Wasim <Bilal.Wasim@imgtec.com>
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/20210701114012.RESEND.2.I2e1bf1b589f9138ba6f89791ed9f1e9f3ddd0a5d@changeid


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