Most of the codebase uses 'CPUState *cpu' or 'CPUState *cs'.
While 'cpu_state' is kind of explicit, it makes the code
harder to review. Simply rename as 'cs'.

Acked-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20230624174121.11508-16-philmd@linaro.org>