mmc: MMC_USDHI6ROL0 should depend on HAS_DMA

If NO_DMA=y:

    drivers/built-in.o: In function `usdhi6_dma_setup':
    usdhi6rol0.c:(.text+0x5c35fc): undefined reference to `dma_map_sg'
    drivers/built-in.o: In function `usdhi6_dma_stop_unmap':
    usdhi6rol0.c:(.text+0x5c3738): undefined reference to `dma_unmap_sg'
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/Kconfig

@@ -702,6 +702,7 @@ config MMC_WMT
 
 config MMC_USDHI6ROL0
 	tristate "Renesas USDHI6ROL0 SD/SDIO Host Controller support"
+	depends on HAS_DMA
 	help
 	  This selects support for the Renesas USDHI6ROL0 SD/SDIO
 	  Host Controller