drm/msm/disp/dpu1/dpu_vbif: Fix a couple of function param descriptions

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

 drivers/gpu/drm/msm/disp/dpu1/dpu_vbif.c:150: warning: Function parameter or member 'dpu_kms' not described in 'dpu_vbif_set_ot_limit'
 drivers/gpu/drm/msm/disp/dpu1/dpu_vbif.c:150: warning: Excess function parameter 'vbif' description in 'dpu_vbif_set_ot_limit'

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: 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>
Signed-off-by: Rob Clark <robdclark@chromium.org>