mmc: descend into drivers/mmc only when CONFIG_MMC is enabled

This simplifies makefiles.  Also, arrange the order of objects in
drivers/mmc/Makefile so that the framework objects are listed before
drivers.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/drivers/mmc/Makefile b/drivers/mmc/Makefile
index 75a7cd3..a078649 100644
--- a/drivers/mmc/Makefile
+++ b/drivers/mmc/Makefile
@@ -5,17 +5,24 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 
-ifdef CONFIG_DM_MMC
-obj-$(CONFIG_MMC) += mmc-uclass.o
-endif
+obj-y += mmc.o
+obj-$(CONFIG_DM_MMC) += mmc-uclass.o
 
 ifndef CONFIG_BLK
-obj-$(CONFIG_MMC) += mmc_legacy.o
+obj-y += mmc_legacy.o
+endif
+
+obj-$(CONFIG_SUPPORT_EMMC_BOOT) += mmc_boot.o
+
+ifdef CONFIG_SPL_BUILD
+obj-$(CONFIG_SPL_MMC_BOOT) += fsl_esdhc_spl.o
+obj-$(CONFIG_SPL_SAVEENV) += mmc_write.o
+else
+obj-y += mmc_write.o
 endif
 
 obj-$(CONFIG_ARM_PL180_MMCI) += arm_pl180_mmci.o
 obj-$(CONFIG_MMC_DAVINCI)		+= davinci_mmc.o
-
 obj-$(CONFIG_MMC_DW)			+= dw_mmc.o
 obj-$(CONFIG_MMC_DW_EXYNOS)		+= exynos_dw_mmc.o
 obj-$(CONFIG_MMC_DW_K3)			+= hi6220_dw_mmc.o
@@ -23,10 +30,6 @@
 obj-$(CONFIG_MMC_DW_SOCFPGA)		+= socfpga_dw_mmc.o
 obj-$(CONFIG_FSL_ESDHC) += fsl_esdhc.o
 obj-$(CONFIG_FTSDC010) += ftsdc010_mci.o
-obj-$(CONFIG_MMC) += mmc.o
-ifdef CONFIG_SUPPORT_EMMC_BOOT
-obj-$(CONFIG_MMC) += mmc_boot.o
-endif
 obj-$(CONFIG_GENERIC_ATMEL_MCI) += gen_atmel_mci.o
 obj-$(CONFIG_MMC_MESON_GX) += meson_gx_mmc.o
 obj-$(CONFIG_MMC_SPI) += mmc_spi.o
@@ -42,13 +45,6 @@
 obj-$(CONFIG_SH_MMCIF) += sh_mmcif.o
 obj-$(CONFIG_SH_SDHI) += sh_sdhi.o
 
-ifdef CONFIG_SPL_BUILD
-obj-$(CONFIG_SPL_MMC_BOOT) += fsl_esdhc_spl.o
-obj-$(CONFIG_SPL_SAVEENV) += mmc_write.o
-else
-obj-$(CONFIG_MMC) += mmc_write.o
-endif
-
 # SDHCI
 obj-$(CONFIG_MMC_SDHCI)			+= sdhci.o
 obj-$(CONFIG_MMC_SDHCI_ATMEL)		+= atmel_sdhci.o