memory: mtk-smi: mt8195: Add initial setting for smi-larb

To improve the performance, We add some initial setting for smi larbs.
there are two part:
1), Each port has the special ostd(outstanding) value in each larb.
2), Two general settings for each larb.
   a. THRT_UPDATE: the value in bits[7:4] of 0x24 is not so good.
   The HW default is 4, and we expect it is 5, thus, add a flag to update
   it. This is only a DE recommendatory value, not a actual issue.
   The register name(THRT_CON) means: throttling control, and the field
   RD_NU_LMT means: Read Non-ultra commands limit.
   This change means update the Read non-ultra command from 4 to 5 here.

   b. SW_FLAG: Set 1 to the FLAG register. this is only for helping
   debug. We could confirm if the larb is reset from this value is 1 or 0.

In some SoC, this setting maybe changed dynamically for some special case
like 4K, and this initial setting is enough in mt8195.

Signed-off-by: Yong Wu <yong.wu@mediatek.com>
Link: https://lore.kernel.org/r/20210914113703.31466-13-yong.wu@mediatek.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>