regulator: qcom-rpmh: Add support for SDX55

Add support from RPMH regulators found in SDX55 platform

Signed-off-by: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20201126093018.1085594-2-vkoul@kernel.org


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