target/arm: Remove iwmmxt helper functions

Remove the iwmmxt helper functions which are no longer called now
that we have removed the associated translate.c handling.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20250828140422.3271703-4-peter.maydell@linaro.org
3 files changed