mmc: core: Only set maximum DMA segment size if DMA is supported

Since upstream commit 334304ac ("dma-mapping: don't return errors
from dma_set_max_seg_size") calling dma_set_max_seg_size() on a device
not supporting DMA results in a warning traceback. This is seen when
booting the sifive_u machine from SD. The underlying SPI controller
(sifive,spi0 compatible) explicitly sets dma_mask to NULL.

Avoid the backtrace by only calling dma_set_max_seg_size() if DMA is
supported.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Fixes: 334304ac ("dma-mapping: don't return errors from dma_set_max_seg_size")
Link: https://lore.kernel.org/r/20240924210123.2288529-1-linux@roeck-us.net


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