spi: sh-msiof: Remove "renesas,msiof-sh7724" from bindings

It's not implemented in the driver, so it's a bad example.

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mark Brown <broonie@linaro.org>