drm/msm/disp/dpu1/dpu_formats: Demote non-conformant kernel-doc header

Fixes the following W=1 kernel build warning(s):

 drivers/gpu/drm/msm/disp/dpu1/dpu_formats.c:50: warning: Function parameter or member 'fmt' not described in 'INTERLEAVED_RGB_FMT'
 drivers/gpu/drm/msm/disp/dpu1/dpu_formats.c:50: warning: Function parameter or member 'a' not described in 'INTERLEAVED_RGB_FMT'
 drivers/gpu/drm/msm/disp/dpu1/dpu_formats.c:50: warning: Function parameter or member 'r' not described in 'INTERLEAVED_RGB_FMT'
 drivers/gpu/drm/msm/disp/dpu1/dpu_formats.c:50: warning: Function parameter or member 'g' not described in 'INTERLEAVED_RGB_FMT'
 drivers/gpu/drm/msm/disp/dpu1/dpu_formats.c:50: warning: Function parameter or member 'b' not described in 'INTERLEAVED_RGB_FMT'
 drivers/gpu/drm/msm/disp/dpu1/dpu_formats.c:50: warning: Function parameter or member 'e0' not described in 'INTERLEAVED_RGB_FMT'
 drivers/gpu/drm/msm/disp/dpu1/dpu_formats.c:50: warning: Function parameter or member 'e1' not described in 'INTERLEAVED_RGB_FMT'
 drivers/gpu/drm/msm/disp/dpu1/dpu_formats.c:50: warning: Function parameter or member 'e2' not described in 'INTERLEAVED_RGB_FMT'
 drivers/gpu/drm/msm/disp/dpu1/dpu_formats.c:50: warning: Function parameter or member 'e3' not described in 'INTERLEAVED_RGB_FMT'
 drivers/gpu/drm/msm/disp/dpu1/dpu_formats.c:50: warning: Function parameter or member 'uc' not described in 'INTERLEAVED_RGB_FMT'
 drivers/gpu/drm/msm/disp/dpu1/dpu_formats.c:50: warning: Function parameter or member 'alpha' not described in 'INTERLEAVED_RGB_FMT'
 drivers/gpu/drm/msm/disp/dpu1/dpu_formats.c:50: warning: Function parameter or member 'bp' not described in 'INTERLEAVED_RGB_FMT'
 drivers/gpu/drm/msm/disp/dpu1/dpu_formats.c:50: warning: Function parameter or member 'flg' not described in 'INTERLEAVED_RGB_FMT'
 drivers/gpu/drm/msm/disp/dpu1/dpu_formats.c:50: warning: Function parameter or member 'fm' not described in 'INTERLEAVED_RGB_FMT'
 drivers/gpu/drm/msm/disp/dpu1/dpu_formats.c:50: warning: Function parameter or member 'np' not described in 'INTERLEAVED_RGB_FMT'

Cc: Rob Clark <robdclark@gmail.com>
Cc: Sean Paul <sean@poorly.run>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Fritz Koenig <frkoenig@google.com>
Cc: linux-arm-msm@vger.kernel.org
Cc: dri-devel@lists.freedesktop.org
Cc: freedreno@lists.freedesktop.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Abhinav Kumar <abhinavk@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>