drm/radeon: wait for moving fence after pinning

commit 4b41726a upstream.

We actually need to wait for the moving fence after pinning
the BO to make sure that the pin is completed.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
References: https://lore.kernel.org/dri-devel/20210621151758.2347474-1-daniel.vetter@ffwll.ch/
CC: stable@kernel.org
Link: https://patchwork.freedesktop.org/patch/msgid/20210622114506.106349-2-christian.koenig@amd.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>