virtio-gpu: call cleanup mapping function in resource destroy

If the guest destroy the resource before detach banking, the 'iov'
and 'addrs' field in resource is not freed thus leading memory
leak issue. This patch avoid this.
Signed-off-by: NLi Qiang <liq3ea@gmail.com>
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 1480386565-10077-1-git-send-email-liq3ea@gmail.com
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>

hw/display/virtio-gpu.c

@@ -28,6 +28,8 @@
 static struct virtio_gpu_simple_resource*
 virtio_gpu_find_resource(VirtIOGPU *g, uint32_t resource_id);
 
+static void virtio_gpu_cleanup_mapping(struct virtio_gpu_simple_resource *res);
+
 #ifdef CONFIG_VIRGL
 #include <virglrenderer.h>
 #define VIRGL(_g, _virgl, _simple, ...)                     \
@@ -364,6 +366,7 @@ static void virtio_gpu_resource_destroy(VirtIOGPU *g,
                                         struct virtio_gpu_simple_resource *res)
 {
     pixman_image_unref(res->image);
+    virtio_gpu_cleanup_mapping(res);
     QTAILQ_REMOVE(&g->reslist, res, next);
     g->hostmem -= res->hostmem;
     g_free(res);