mmc: renesas_sdhi: make 'dmac_only_one_rx' a quirk

After Shimoda-san's much appreciated refactoring of the quirk handling,
we can convert now 'dmac_only_one_rx' from an ugly global flag to a
regular quirk. This makes quirk handling more consistent and easier to
maintain. After this patch, soc_dma_quirks is completely gone, hooray!

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20220320123016.57991-7-wsa+renesas@sang-engineering.com


Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>