spirv/vtn_cfg.c: Include util/debug.h for env_var_as_boolean.

Fixes https://gitlab.freedesktop.org/mesa/mesa/-/issues/3414

Reviewed-by: Dave Airlie <airlied@redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6331>
1 file changed