Add a PHY configuration sequence for the sc8280xp which uses a Qualcomm
Gen 2 version 1.1 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: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>