Use enum dma_transfer_direction as required by dmaengine_prep_slave_sg()
instead of enum dma_data_direction.  This won't change behavior in
practice as the enum values are equivalent.

This fixes two warnings when building with clang:
  drivers/spi/spi-sh-msiof.c:755:27: warning: implicit conversion from enumeration
      type 'enum dma_data_direction' to different enumeration type
      'enum dma_transfer_direction' [-Wenum-conversion]
					rx->sgl, rx->nents, DMA_FROM_DEVICE,
							    ^~~~~~~~~~~~~~~
  drivers/spi/spi-sh-msiof.c:772:27: warning: implicit conversion from enumeration
      type 'enum dma_data_direction' to different enumeration type
      'enum dma_transfer_direction' [-Wenum-conversion]
					tx->sgl, tx->nents, DMA_TO_DEVICE,
							    ^~~~~~~~~~~~~

Based on commit 768d59f5 ("spi: rspi: use correct enum for DMA
transfer direction").
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Mark Brown <broonie@kernel.org>