Instead of using wined3d_texture_update_desc(). This is safe, because:

* ddraw never exposes wined3d textures directly, and always retrieves them
  directly from wined3d when rendering.

* d3d8 and d3d9 (non-extended) will only resize buffers during a reset, and
  resetting is forbidden if the application holds any references to the
  backbuffers. RTVs are also replaced during a reset, so there is no concern
  about retrieving the old RTVs from the device state.

* d3d9ex allows resetting while holding references to the backbuffers, but tests
  (fixed by this patch) show that the backbuffers should in fact be recreated.

* dxgi forbids holding references to back buffers during ResizeBuffers(),
  including indirect references via command lists or device contexts.