ASoC: SOF: mediatek: mt8186 modify dram type as non-cache

To prevent incorrect access between the host and DSP sides, we need to
modify DRAM as a non-cache memory type. Additionally, we can retrieve
the size of shared DMA from the device tree.

Signed-off-by: Trevor Wu <trevor.wu@mediatek.com>
Reviewed-by: Yaochun Hung <yc.hung@mediatek.com>
Reviewed-by: Kuan-Hsun Cheng <Allen-KH.Cheng@mediatek.com>
Link: https://lore.kernel.org/r/20230803075028.32170-1-trevor.wu@mediatek.com
Signed-off-by: Mark Brown <broonie@kernel.org>