drm/v3d/v3d_sched: Demote non-conformant kernel-doc header

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

 drivers/gpu/drm/v3d/v3d_sched.c:75: warning: Function parameter or member 'sched_job' not described in 'v3d_job_dependency'
 drivers/gpu/drm/v3d/v3d_sched.c:75: warning: Function parameter or member 's_entity' not described in 'v3d_job_dependency'

Cc: Eric Anholt <eric@anholt.net>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-media@vger.kernel.org
Cc: linaro-mm-sig@lists.linaro.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20201116174112.1833368-37-lee.jones@linaro.org

drivers/gpu/drm/v3d/v3d_sched.c

@@ -63,8 +63,8 @@ v3d_job_free(struct drm_sched_job *sched_job)
 	v3d_job_put(job);
 }
 
-/**
- * v3d_job_dependency - Returns the fences that the job depends on, one by one.
+/*
+ * Returns the fences that the job depends on, one by one.
  *
  * If placed in the scheduler's .dependency method, the corresponding
  * .run_job won't be called until all of them have been signaled.