drm/vmwgfx: Remove set but not used variable 'file_priv'

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/gpu/drm/vmwgfx/vmwgfx_fence.c: In function 'vmw_event_fence_action_seq_passed':
drivers/gpu/drm/vmwgfx/vmwgfx_fence.c:909:19: warning:
 variable 'file_priv' set but not used [-Wunused-but-set-variable]
  struct drm_file *file_priv;

It not used any more since
commit fb740cf2 ("drm: Create drm_send_event helpers")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>

drivers/gpu/drm/vmwgfx/vmwgfx_fence.c

@@ -906,13 +906,10 @@ static void vmw_event_fence_action_seq_passed(struct vmw_fence_action *action)
 		container_of(action, struct vmw_event_fence_action, action);
 	struct drm_device *dev = eaction->dev;
 	struct drm_pending_event *event = eaction->event;
-	struct drm_file *file_priv;
-
 
 	if (unlikely(event == NULL))
 		return;
 
-	file_priv = event->file_priv;
 	spin_lock_irq(&dev->event_lock);
 
 	if (likely(eaction->tv_sec != NULL)) {