drm/vmwgfx/vmwgfx_ldu: Supply descriptions for 'state' function parameter

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

 drivers/gpu/drm/vmwgfx/vmwgfx_ldu.c:55: warning: cannot understand function prototype: 'struct vmw_legacy_display_unit '
 drivers/gpu/drm/vmwgfx/vmwgfx_ldu.c:218: warning: Function parameter or member 'state' not described in 'vmw_ldu_crtc_atomic_enable'
 drivers/gpu/drm/vmwgfx/vmwgfx_ldu.c:228: warning: Function parameter or member 'state' not described in 'vmw_ldu_crtc_atomic_disable'

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/20210115181313.3431493-14-lee.jones@linaro.org

drivers/gpu/drm/vmwgfx/vmwgfx_ldu.c

@@ -49,7 +49,7 @@ struct vmw_legacy_display {
 	struct vmw_framebuffer *fb;
 };
 
-/**
+/*
  * Display unit using the legacy register interface.
  */
 struct vmw_legacy_display_unit {
@@ -206,6 +206,7 @@ static void vmw_ldu_crtc_mode_set_nofb(struct drm_crtc *crtc)
  * vmw_ldu_crtc_atomic_enable - Noop
  *
  * @crtc: CRTC associated with the new screen
+ * @state: Unused
  *
  * This is called after a mode set has been completed.  Here's
  * usually a good place to call vmw_ldu_add_active/vmw_ldu_del_active
@@ -221,6 +222,7 @@ static void vmw_ldu_crtc_atomic_enable(struct drm_crtc *crtc,
  * vmw_ldu_crtc_atomic_disable - Turns off CRTC
  *
  * @crtc: CRTC to be turned off
+ * @state: Unused
  */
 static void vmw_ldu_crtc_atomic_disable(struct drm_crtc *crtc,
 					struct drm_atomic_state *state)