drm/msm/dpu1: don't choke on disabling the writeback connector

During suspend/resume process all connectors are explicitly disabled and
then reenabled. However resume fails because of the connector_status check:

[dpu error]connector not connected 3
[drm:drm_mode_config_helper_resume [drm_kms_helper]] *ERROR* Failed to resume (-22)

It doesn't make sense to check for the Writeback connected status (and
other drivers don't perform such check), so drop the check.

It wasn't a problem before the commit 71174f3 ("drm/msm/dpu: move
writeback's atomic_check to dpu_writeback.c"), since encoder's
atomic_check() is called under a different conditions that the
connector's atomic_check() (e.g. it is not called if there is no
connected CRTC or if the corresponding connector is not a part of the
new state).

Fixes: 71174f3 ("drm/msm/dpu: move writeback's atomic_check to dpu_writeback.c")
Cc: stable@vger.kernel.org
Reported-by: Leonard Lausen <leonard@lausen.nl>
Closes: https://gitlab.freedesktop.org/drm/msm/-/issues/57
Tested-by: Leonard Lausen <leonard@lausen.nl> # on sc7180 lazor
Tested-by: György Kurucz <me@kuruczgy.com>
Reviewed-by: Johan Hovold <johan+linaro@kernel.org>
Tested-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Tested-by: Jessica Zhang <quic_jesszhan@quicinc.com> # Trogdor (sc7180)
Patchwork: https://patchwork.freedesktop.org/patch/627828/
Link: https://lore.kernel.org/r/20241209-dpu-fix-wb-v4-1-7fe93059f9e0@linaro.org
Signed-off-by: Abhinav Kumar <quic_abhinavk@quicinc.com>

drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.c

@@ -42,9 +42,6 @@ static int dpu_wb_conn_atomic_check(struct drm_connector *connector,
 	if (!conn_state || !conn_state->connector) {
 		DPU_ERROR("invalid connector state\n");
 		return -EINVAL;
-	} else if (conn_state->connector->status != connector_status_connected) {
-		DPU_ERROR("connector not connected %d\n", conn_state->connector->status);
-		return -EINVAL;
 	}
 
 	crtc = conn_state->crtc;