arm: hisi_defconfig: remove CONFIG_MMC_DW_IDMAC

DesignWare MMC Controller's transfer mode should be decided
at runtime instead of compile-time. So we remove this config
option and read dw_mmc's register to select DMA master.
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Acked-by: Wei Xu <xuwei5@hisilicon.com>
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

arch/arm/configs/hisi_defconfig

@@ -69,7 +69,6 @@ CONFIG_NOP_USB_XCEIV=y
 CONFIG_MMC=y
 CONFIG_RTC_CLASS=y
 CONFIG_MMC_DW=y
-CONFIG_MMC_DW_IDMAC=y
 CONFIG_MMC_DW_PLTFM=y
 CONFIG_RTC_DRV_PL031=y
 CONFIG_DMADEVICES=y