drm/msm/dpu: set pdpu->is_rt_pipe early in dpu_plane_sspp_atomic_update()

The function dpu_plane_sspp_atomic_update() updates pdpu->is_rt_pipe
flag, but after the commit 854f6f1c ("drm/msm/dpu: update the qos
remap only if the client type changes") it sets the flag late, after all
the qos functions have updated QoS programming. Move the flag update
back to the place where it happened before the mentioned commit to let
the pipe be programmed according to its current RT/non-RT state.

Fixes: 854f6f1c

 ("drm/msm/dpu: update the qos remap only if the client type changes")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/516239/
Link: https://lore.kernel.org/r/20221229191856.3508092-2-dmitry.baryshkov@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>