mmc: MMC_BLOCK_MINORS should depend on MMC_BLOCK.

Signed-off-by: Chris Ball <cjb@laptop.org>
Tested-by: Chris Ball <cjb@laptop.org>
Acked-by: Olof Johansson <olof@lixom.net>

drivers/mmc/card/Kconfig

@@ -16,6 +16,7 @@ config MMC_BLOCK
 
 config MMC_BLOCK_MINORS
 	int "Number of minors per block device"
+	depends on MMC_BLOCK
 	range 4 256
 	default 8
 	help