phy: phy-mtk-tphy: fix the phy type setting issue

phy: phy-mtk-tphy: fix the phy type setting issue

The PHY type is not set if the index is non zero, prepare type
value according to the index, like as mask value.

Fixes: 39099a443358 ("phy: phy-mtk-tphy: support type switch by pericfg")
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20220914060746.10004-7-chunfeng.yun@mediatek.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>