linux-imx

spi: octeon: Remove empty octeon_spi_nop_transfer_hardware function

Both prepare_transfer_hardware and unprepare_transfer_hardware callbacks are
optional, so we don't need to implement an empty function for them.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@linaro.org>