drm/msm/dp: use dp_ctrl_off_link_stream during PHY compliance test run

DP cable should always connect to DPU during the entire PHY compliance
testing run. Since DP PHY compliance test is executed at irq_hpd event
context, dp_ctrl_off_link_stream() should be used instead of dp_ctrl_off().
dp_ctrl_off() is used for unplug event which is triggered when DP cable is
dis connected.

Changes in V2:
-- add fixes statement

Fixes: f21c8a27

 ("drm/msm/dp: handle irq_hpd with sink_count = 0 correctly")

Signed-off-by: Kuogee Hsieh <khsieh@codeaurora.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/1626191647-13901-2-git-send-email-khsieh@codeaurora.org
Signed-off-by: Rob Clark <robdclark@chromium.org>