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/board/bosch/shc/board.c b/board/bosch/shc/board.c
index e90693f..38577f3 100644
--- a/board/bosch/shc/board.c
+++ b/board/bosch/shc/board.c
@@ -632,7 +632,7 @@
 	leds_set_finish();
 }
 
-#if defined(CONFIG_GENERIC_MMC)
+#if defined(CONFIG_MMC)
 int board_mmc_init(bd_t *bis)
 {
 	int ret;