obs-ffmpeg: Set DRI devices and their name persistently

retrieving the DRI devices from /dev/dri/by-path/ instead of
/dev/dri/renderDXXX. This enable us to use lspci to get the device
name as well.

.github/workflows/main.yml

@@ -441,7 +441,8 @@ jobs:
            qtbase5-private-dev \
            libqt5svg5-dev \
            swig \
-           libcmocka-dev
+           libcmocka-dev \
+           libpci-dev
       - name: 'Restore Chromium Embedded Framework from cache'
         id: cef-cache
         uses: actions/cache@v2.1.2