arm64: dts: hikey: Add hi655x pmic dts node

Add the mfd hi655x dts node and regulator support on hi6220 platform.

Signed-off-by: Chen Feng <puck.chen@hisilicon.com>
Signed-off-by: Fei Wang <w.f@huawei.com>
Signed-off-by: Xinwei Kong <kong.kongxinwei@hisilicon.com>
Signed-off-by: Guodong Xu <guodong.xu@linaro.org>
Reviewed-by: Haojian Zhuang <haojian.zhuang@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>