soc: mediatek: mtk-svs: use svs get efuse common function

SVS might need to read both svs efuse and thermal efuse on the probe flow.
Therefore, add a common efuse read function to remove the superfluous
codes.

Signed-off-by: Roger Lu <roger.lu@mediatek.com>
Link: https://lore.kernel.org/r/20230202124104.16504-2-roger.lu@mediatek.com


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