spi: spi-qcom-qspi: Add mem_ops to avoid PIO for badly sized reads

spi: spi-qcom-qspi: Add mem_ops to avoid PIO for badly sized reads

In the patch ("spi: spi-qcom-qspi: Fallback to PIO for xfers that
aren't multiples of 4 bytes") we detect reads that we can't handle
properly and fallback to PIO mode. While that's correct behavior, we
can do better by adding "spi_controller_mem_ops" for our
controller. Once we do this then the caller will give us a transfer
that's a multiple of 4-bytes so we can DMA.

Fixes: b5762d95607e ("spi: spi-qcom-qspi: Add DMA mode support")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Vijaya Krishna Nivarthi <quic_vnivarth@quicinc.com>
Link: https://lore.kernel.org/r/20230725110226.2.Id4a39804e01e4a06dae9b73fd2a5194c4c7ea453@changeid
Signed-off-by: Mark Brown <broonie@kernel.org>