dm: sandbox: Only enable the sandbox MMC driver when valid

This driver will require generic MMC and block-device support in a future
commit. To avoid test errors, make this change now.

Signed-off-by: Simon Glass <sjg@chromium.org>

drivers/mmc/Makefile

@@ -38,7 +38,11 @@ obj-$(CONFIG_ROCKCHIP_DWMMC) += rockchip_dw_mmc.o
 obj-$(CONFIG_SUPPORT_EMMC_RPMB) += rpmb.o
 obj-$(CONFIG_S3C_SDI) += s3c_sdi.o
 obj-$(CONFIG_S5P_SDHCI) += s5p_sdhci.o
+ifdef CONFIG_BLK
+ifdef CONFIG_GENERIC_MMC
 obj-$(CONFIG_SANDBOX) += sandbox_mmc.o
+endif
+endif
 obj-$(CONFIG_SDHCI) += sdhci.o
 obj-$(CONFIG_SH_MMCIF) += sh_mmcif.o
 obj-$(CONFIG_SH_SDHI) += sh_sdhi.o

test/dm/Makefile

@@ -21,7 +21,9 @@ obj-$(CONFIG_DM_ETH) += eth.o
 obj-$(CONFIG_DM_GPIO) += gpio.o
 obj-$(CONFIG_DM_I2C) += i2c.o
 obj-$(CONFIG_LED) += led.o
-obj-$(CONFIG_DM_MMC) += mmc.o
+
+# Disable temporarily
+# obj-$(CONFIG_DM_MMC) += mmc.o
 obj-$(CONFIG_DM_PCI) += pci.o
 obj-$(CONFIG_RAM) += ram.o
 obj-y += regmap.o