Update workflow for linux

.github/workflows/build-self-hosted.yml

@@ -181,7 +181,9 @@ jobs:
       - name: Download ggml model
         shell: cmd
         run: |
-          call models\download-ggml-model.cmd %MODEL%
+          cd models
+          call download-ggml-model.cmd %MODEL%
+          cd ..
           if not exist models\ggml-%MODEL%.bin ( echo ERROR: model download failed & exit /b 1 )
 
       - name: Download NPU encoder cache
@@ -221,12 +223,6 @@ jobs:
       - name: Clone
         uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
 
-      - name: Install system deps
-        run: |
-          sudo apt-get update
-          sudo apt-get install -y build-essential cmake git \
-            python3.12 python3.12-venv libboost-filesystem1.74.0
-
       - name: Verify NPU device
         run: |
           lsmod | grep -q amdxdna || { echo "ERROR: amdxdna driver not loaded"; exit 1; }