ARM: dts: marvell: armada: drop incorrect reg in fixed regulators

Fixed regulators are not in some bus and bindings do not allow a "reg"
property.  Move them out of "regulators" node to top-level.

  armada-370-dlink-dns327l.dtb: regulator@1: Unevaluated properties are not allowed ('reg' was unexpected)

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>