target-tilegx: Implement v1multu instruction Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com> Reviewed-by: Richard Henderson <rth@twiddle.net> Message-Id: <1442874414-3578-1-git-send-email-gang.chen.5i5j@gmail.com> Signed-off-by: Richard Henderson <rth@twiddle.net>