In preparation to enabling this driver on x86 devices let's switch
from OF-specific property API to the generic one.
Reviewed-by: NStephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20220526231230.2805147-1-dmitry.torokhov@gmail.comSigned-off-by: NDmitry Torokhov <dmitry.torokhov@gmail.com>