spi: fsl-espi: change return type of fsl_espi_cpu_bufs to void

fsl_espi_cpu_bufs always returns 0, so change the return type to void.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
1 file changed