regulator: Add missing type for 'regulator-microvolt-offset'

'regulator-microvolt-offset' is missing a type definition. The type should
be 'uint32'.

Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220719215010.1875363-1-robh@kernel.org


Signed-off-by: Mark Brown <broonie@kernel.org>