Due to the division of TU_DEBUG options into runtime and envvar options, it limited where options could be set from when TU_DEBUG_FILE was being used. This commit addresses that by allowing the envvar to set runtime debug options even when TU_DEBUG_FILE is active while also allowing the file to set non-runtime options if the file included them at startup. Signed-off-by: Dhruv Mark Collins <mark@igalia.com> Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/37580>