platform/chrome: cros_ec_spi: Drop bits_per_word assignment

platform/chrome: cros_ec_spi: Drop bits_per_word assignment

This is already handed by default in spi_setup() if the bits_per_word is
0, so just drop it to shave off a line.

Cc: Simon Glass <sjg@chromium.org>
Cc: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Cc: Alexandru M Stan <amstan@chromium.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Link: https://lore.kernel.org/r/20201204193540.3047030-3-swboyd@chromium.org
Signed-off-by: Mark Brown <broonie@kernel.org>