drm/msm/dpu: drop enum msm_display_caps

drm/msm/dpu: drop enum msm_display_caps

After the commit 8721277472e4 ("drm/msm: remove unused hotplug and edid
macros from msm_drv.h") the msm_display_caps enum contains two bits
describing whether the encoder should work in video or command mode.
Drop the enum and replace capabilities field in struct msm_display_info
with boolean is_cmd_mode field.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/485454/
Link: https://lore.kernel.org/r/20220507115942.1705872-2-dmitry.baryshkov@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>