drm/msm/dsi: Switch the QCM2290-specific compatible to index autodetection

Now that the logic can handle multiple sets of registers, move
the QCM2290 to the common logic and mark it deprecated. This allows us
to remove a couple of structs, saving some memory.

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Marijn Suijten <marijn.suijten@somainline.org>
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/527656/
Link: https://lore.kernel.org/r/20230307-topic-dsi_qcm-v6-6-70e13b1214fa@linaro.org


Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>