drm/msm/dsi: drop the hpd worker

It makes no sense to have the HPD worker in the MSM DSI driver anymore.
It is only queued from the dsi_host_attach/detach() callbacks, where
it plays no useful role. Either way the panel or next bridge will be
present and will report it's status directly.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/498740/
Link: https://lore.kernel.org/r/20220822174417.292926-1-dmitry.baryshkov@linaro.org


Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>