drm/vmwgfx/vmwgfx_cmdbuf_res: Rename param description and remove another

Also fix a small formatting issue.

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

 drivers/gpu/drm/vmwgfx/vmwgfx_cmdbuf_res.c:83: warning: Function parameter or member 'res_type' not described in 'vmw_cmdbuf_res_lookup'
 drivers/gpu/drm/vmwgfx/vmwgfx_cmdbuf_res.c:83: warning: Excess function parameter 'resource_type' description in 'vmw_cmdbuf_res_lookup'
 drivers/gpu/drm/vmwgfx/vmwgfx_cmdbuf_res.c:161: warning: Excess function parameter 'man' description in 'vmw_cmdbuf_res_revert'
 drivers/gpu/drm/vmwgfx/vmwgfx_cmdbuf_res.c:330: warning: Cannot understand  *

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: dri-devel@lists.freedesktop.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/20210115181313.3431493-36-lee.jones@linaro.org