util: disable glthread in CSGO

util: disable glthread in CSGO

Users have reported a rise in trust factor problems [1] since using
mesa builds containing 6f2017205e62. Until we confirm its not a problem
disable glthread.

[1] https://github.com/ValveSoftware/csgo-osx-linux/issues/2630

Fixes: 6f2017205e62 ("dri: enable glthread + radeonsi workaround for CS:GO")
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/4710

Reviewed-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10540>