We always pass pc2 == dc->npc and r_cond == cpu_cond,
and always set is_br afterward. Infer all of that.
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>