ci: when specifying a driver remove all other ones

If we need to specify a driver, it means several drivers could pick up this gpu;
ensure that the other driver can't accidentally be used.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25434>

.gitlab-ci/common/init-stage2.sh

@@ -7,6 +7,8 @@
 # Second-stage init, used to set up devices and our job environment before
 # running tests.
 
+shopt -s extglob
+
 # Make sure to kill itself and all the children process from this script on
 # exiting, since any console output may interfere with LAVA signals handling,
 # which based on the log console.
@@ -106,6 +108,13 @@ export XDG_CACHE_HOME=/tmp
 # Make sure Python can find all our imports
 export PYTHONPATH=$(python3 -c "import sys;print(\":\".join(sys.path))")
 
+# If we need to specify a driver, it means several drivers could pick up this gpu;
+# ensure that the other driver can't accidentally be used
+if [ -n "$MESA_LOADER_DRIVER_OVERRIDE" ]; then
+  rm /install/lib/dri/!($MESA_LOADER_DRIVER_OVERRIDE)_dri.so
+fi
+ls -l /install/lib/dri/*_dri.so
+
 if [ "$HWCI_FREQ_MAX" = "true" ]; then
   # Ensure initialization of the DRM device (needed by MSM)
   head -0 /dev/dri/renderD128