Since U-Boot is single threaded, we can avoid most of the complexity that comes with handling more than one in-flight TCS. Drop all the rpmh code associated with multi-threading as we'll instead wait for a response on each TCS. Acked-by: Sumit Garg <sumit.garg@linaro.org> Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>