qxl: better cleanup for surface destroy

qxl: better cleanup for surface destroy

Add back a call to qxl_spice_destroy_surface_wait_complete() in qxl_spice_destroy_surface_wait(),
that was removed by commit c480bb7da465186b84d8427e068ef7502e47ffbf

It is needed to complete surface-removal cleanup, for non async.
For async, qxl_spice_destroy_surface_wait_complete is called upon operation completion.

Signed-off-by: Uri Lublin <uril@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
(cherry picked from commit 753b8b0d77ba1b343a35f9679cc777ea10a62bba)

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>