hw/sh4: Remove sh7750_register_io_device() helper

sh7750_register_io_device() was only used by the TC58128
NAND EEPROM which has been removed in the previous commit.
Remove it as unused code.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Yoshinori Sato <ysato@users.sourceforge.jp>
Message-ID: <20240903153959.18392-4-philmd@linaro.org>
2 files changed