[BUG] Intel Arc A380 VAAPI transcoding fails on ls329, works on ls328 #461

Failed to initialise VAAPI connection: -1 (unknown libva error)
Device creation failed: -5
Failed to set value '/dev/dri/renderD128' for option 'vaapi_device': I/O error

### Expected Behavior

_No response_

### Steps To Reproduce

### Steps to reproduce

1. Run `lscr.io/linuxserver/plex:1.43.5.11029-6bf8af3f0-ls329` on Unraid 7.4.0-rc.1.
2. Pass the GPU device to the container:

   ```text
   /dev/dri:/dev/dri
3. Select the Intel Arc A380 as the Plex hardware transcoding device.
4. Verify that the Arc render node is available:
   ls -l /dev/dri/by-path/
   The Arc A380 maps to /dev/dri/renderD128.
5. Run this VAAPI smoke test inside the container:
   docker exec plex \
     "/usr/lib/plexmediaserver/Plex Transcoder" \
     -hide_banner -loglevel error \
     -vaapi_device /dev/dri/renderD128 \
     -f lavfi -i "testsrc2=size=128x128:rate=1" \
     -vf "format=nv12,hwupload" \
     -c:v h264_vaapi \
     -frames:v 1 \
     -f null -
6. The test fails with:
   Failed to initialise VAAPI connection: -1 (unknown libva error)
   Device creation failed: -5
   Failed to set value '/dev/dri/renderD128' for option 'vaapi_device': I/O error
7. Roll back the container image to:
   1.43.4.10903-e5521bd8c-ls328

### Environment

```markdown
- OS: Unraid
- How docker service was installed:
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