mmc: MMC_SH_MMCIF should depend on HAS_DMA

If NO_DMA=y:

    drivers/built-in.o: In function `sh_mmcif_start_dma_tx':
    sh_mmcif.c:(.text+0x5a3286): undefined reference to `dma_map_sg'
    drivers/built-in.o: In function `sh_mmcif_start_dma_rx':
    sh_mmcif.c:(.text+0x5a33fc): undefined reference to `dma_map_sg'
    drivers/built-in.o: In function `sh_mmcif_end_cmd':
    sh_mmcif.c:(.text+0x5a3668): undefined reference to `dma_unmap_sg'

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>