drm/msm/dp: rename second dp_display_enable()'s argument

drm/msm/dp: rename second dp_display_enable()'s argument

To follow up recent changes, rename (and change type of) second
dp_display_enable()'s argument from generic u32 data to bool
force_link_train, which is later passed to dp_ctrl_on_stream().

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Kuogee Hsieh <quic_khsieh@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/490102/
Link: https://lore.kernel.org/r/20220617232434.1139950-2-dmitry.baryshkov@linaro.org
Signed-off-by: Rob Clark <robdclark@chromium.org>