dm: mmc: Enable DM_MMC_OPS by default with DM_MMC

These two options go together and it is best to do the conversion in one
step. So enable DM_MMC_OPS by default if DM_MMC is enabled.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/k2g_evm_defconfig b/configs/k2g_evm_defconfig
index 27659ba..3e5630b 100644
--- a/configs/k2g_evm_defconfig
+++ b/configs/k2g_evm_defconfig
@@ -37,6 +37,7 @@
 CONFIG_DM=y
 # CONFIG_BLK is not set
 CONFIG_DM_MMC=y
+# CONFIG_DM_MMC_OPS is not set
 CONFIG_DM_SPI_FLASH=y
 CONFIG_SPI_FLASH=y
 CONFIG_SPI_FLASH_BAR=y