arm64: dts: mediatek: mt8173-evb: Fix MT6397 PMIC sub-node names

[ Upstream commit 9545ba142865b9099d43c972b9ebcf463606499a ]

The MT6397 PMIC bindings specify exact names for its sub-nodes. The
names used in the current dts don't match, causing a validation error.

Fix up the names. Also drop the label for the regulators node, since
any reference should be against the individual regulator sub-nodes.

Fixes: 16ea61fc ("arm64: dts: mt8173-evb: Add PMIC support")
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Link: https://lore.kernel.org/r/20241210092614.3951748-2-wenst@chromium.org


Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>