drm/vmwgfx/vmwgfx_fence: Add, remove and demote various documentation params/headers

drm/vmwgfx/vmwgfx_fence: Add, remove and demote various documentation params/headers

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

 drivers/gpu/drm/vmwgfx/vmwgfx_fence.c:82: warning: Function parameter or member 'event' not described in 'vmw_event_fence_action'
 drivers/gpu/drm/vmwgfx/vmwgfx_fence.c:113: warning: Function parameter or member 'f' not described in 'vmw_fence_obj_destroy'
 drivers/gpu/drm/vmwgfx/vmwgfx_fence.c:261: warning: Function parameter or member 'work' not described in 'vmw_fence_work_func'
 drivers/gpu/drm/vmwgfx/vmwgfx_fence.c:720: warning: Function parameter or member 'fman' not described in 'vmw_fence_fifo_down'
 drivers/gpu/drm/vmwgfx/vmwgfx_fence.c:963: warning: Function parameter or member 'fence' not described in 'vmw_fence_obj_add_action'
 drivers/gpu/drm/vmwgfx/vmwgfx_fence.c:963: warning: Function parameter or member 'action' not described in 'vmw_fence_obj_add_action'
 drivers/gpu/drm/vmwgfx/vmwgfx_fence.c:1021: warning: Function parameter or member 'tv_sec' not described in 'vmw_event_fence_action_queue'
 drivers/gpu/drm/vmwgfx/vmwgfx_fence.c:1021: warning: Function parameter or member 'tv_usec' not described in 'vmw_event_fence_action_queue'

Cc: VMware Graphics <linux-graphics-maintainer@vmware.com>
Cc: Roland Scheidegger <sroland@vmware.com>
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: Zack Rusin <zackr@vmware.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210115181313.3431493-27-lee.jones@linaro.org