spi: kirkwood: Get drvdata in .ofdata_to_platdata

Get the is_errata_50mhz_ac in .ofdata_to_platdata, and
reuse it in .set_mode this can eventually initialized
dt code at once and adding room to add platdata.

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
1 file changed