Don't try to read pixels from DMA-BUF texture

Merged Jonas Ådahl requested to merge jadahl/mutter:wip/dont-get-data-from-dmabuf into master

Seems that we can't get pixels from DMA-BUF textures according to, so lets not.

Haven't tested if this actually fixes the issue, as when doing a quick test, it didn't reproduce to begin with.

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