CI Linux FFmpeg: do not build VPL tools

tools are not required, reducing dependencies and build time

see failed run:
<https://github.com/CESNET/UltraGrid/actions/runs/7386262548/job/20092516404>

.github/scripts/Linux/download_build_ffmpeg.sh

@@ -42,7 +42,7 @@ install_onevpl() {(
         git clone --depth 1 https://github.com/oneapi-src/oneVPL
         mkdir oneVPL/build
         cd oneVPL/build
-        cmake ..
+        cmake -DBUILD_TOOLS=OFF ..
         cmake --build . --config Release --parallel
         sudo cmake --build . --config Release --target install
 )}

.github/scripts/Linux/prepare.sh

@@ -46,8 +46,6 @@ sudo apt install $ffmpeg_build_dep libdav1d-dev libde265-dev
 sudo apt-get -y remove 'libavcodec*' 'libavutil*' 'libswscale*' libvpx-dev 'libx264*' nginx
 # own x264 build
 sudo apt --no-install-recommends install asciidoc xmlto
-# openVPL
-sudo apt install libva-dev libdrm-dev libx11-dev libx11-xcb-dev libxcb-present-dev libxcb-dri3-dev wayland-protocols
 
 sudo apt install qtbase5-dev