spi: sh-msiof: use dev in sh_msiof_spi_probe()

sh_msiof_spi_probe() is using priv->dev everywhere,
but it makes code long. Create struct device *dev and use it.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/87y0vy2x0o.wl-kuninori.morimoto.gx@renesas.com


Signed-off-by: Mark Brown <broonie@kernel.org>