drm/msm/dpu: move INTF tearing checks to dpu_encoder_phys_cmd_init

As the INTF is fixed at the encoder creation time, we can move the
check whether INTF supports tearchck to dpu_encoder_phys_cmd_init().
This function can return an error if INTF doesn't have required feature.
Performing this check in dpu_encoder_phys_cmd_tearcheck_config() is less
useful, as this function returns void.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Patchwork: https://patchwork.freedesktop.org/patch/555553/
Link: https://lore.kernel.org/r/20230904020454.2945667-9-dmitry.baryshkov@linaro.org