media: qcom: camss: csiphy-3ph: Add Gen2 v2.1.2 two-phase MIPI CSI-2 DPHY support

Add a PHY configuration sequence and PHY resource for the sm8550 which
uses a Qualcomm Gen 2 version 2.1.2 CSI-2 PHY.

The PHY can be configured as two phase or three phase in C-PHY or D-PHY
mode. This configuration supports two-phase D-PHY mode.

Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Depeng Shao <quic_depengs@quicinc.com>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>