mmc: replace CONFIG_GENERIC_MMC with CONFIG_MMC

Now CONFIG_GENERIC_MMC and CONFIG_MMC match for all defconfig.
We do not need two options for the same feature.  Deprecate the
former.

This commit was generated with the sed script 's/GENERIC_MMC/MMC/'
and manual fixup of drivers/mmc/Kconfig.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/drivers/mmc/davinci_mmc.c b/drivers/mmc/davinci_mmc.c
index 9edb668..dd78429 100644
--- a/drivers/mmc/davinci_mmc.c
+++ b/drivers/mmc/davinci_mmc.c
@@ -347,7 +347,7 @@
 	return 0;
 }
 
-/* Set buswidth or clock as indicated by the GENERIC_MMC framework */
+/* Set buswidth or clock as indicated by the MMC framework */
 static int dmmc_set_ios(struct mmc *mmc)
 {
 	struct davinci_mmc *host = mmc->priv;