target/mips: Remove unused 'hw/misc/mips_itu.h' header

Since commit e1152f8166 ("target/mips: Remove helpers accessing
SAAR registers") this header is not needed.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Message-Id: <20240529155216.5574-1-philmd@linaro.org>
1 file changed