arm64: dts: mediatek: mt8183-kukui: Assign sram supply to mfg_async pd

Add a phandle to the MT8183_POWER_DOMAIN_MFG_ASYNC power domain and
assign the GPU VSRAM supply to this in mt8183-kukui: this allows to
keep the sram powered up while the GPU is used.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20220623123850.110225-3-angelogioacchino.delregno@collabora.com


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