mmc: Makefile: Fix EXTRA_CFLAGS assignment

The EXTRA_CFLAGS assignment in mmc/Makefile was not accomplishing
anything because this flag only has effect on sources at the same level
as the makefile (i.e., per directory). Since card/, core/, and host/
rely on MMC_DEBUG, the subdir-ccflags-y variant seems to be the
appropriate choice.
Signed-off-by: Nmatt mooney <mfm@muteddisk.com>
Signed-off-by: NChris Ball <cjb@laptop.org>

drivers/mmc/Makefile

@@ -2,9 +2,7 @@
 # Makefile for the kernel mmc device drivers.
 #
 
-ifeq ($(CONFIG_MMC_DEBUG),y)
-	EXTRA_CFLAGS		+= -DDEBUG
-endif
+subdir-ccflags-$(CONFIG_MMC_DEBUG) := -DDEBUG
 
 obj-$(CONFIG_MMC)		+= core/
 obj-$(CONFIG_MMC)		+= card/

drivers/mmc/card/Makefile

@@ -2,10 +2,6 @@
 # Makefile for MMC/SD card drivers
 #
 
-ifeq ($(CONFIG_MMC_DEBUG),y)
-	EXTRA_CFLAGS		+= -DDEBUG
-endif
-
 obj-$(CONFIG_MMC_BLOCK)		+= mmc_block.o
 mmc_block-objs			:= block.o queue.o
 obj-$(CONFIG_MMC_TEST)		+= mmc_test.o

drivers/mmc/core/Makefile

@@ -2,10 +2,6 @@
 # Makefile for the kernel mmc core.
 #
 
-ifeq ($(CONFIG_MMC_DEBUG),y)
-	EXTRA_CFLAGS		+= -DDEBUG
-endif
-
 obj-$(CONFIG_MMC)		+= mmc_core.o
 mmc_core-y			:= core.o bus.o host.o \
 				   mmc.o mmc_ops.o sd.o sd_ops.o \

drivers/mmc/host/Makefile

@@ -2,10 +2,6 @@
 # Makefile for MMC/SD host controller drivers
 #
 
-ifeq ($(CONFIG_MMC_DEBUG),y)
-	EXTRA_CFLAGS		+= -DDEBUG
-endif
-
 obj-$(CONFIG_MMC_ARMMMCI)	+= mmci.o
 obj-$(CONFIG_MMC_PXA)		+= pxamci.o
 obj-$(CONFIG_MMC_IMX)		+= imxmmc.o