misc: change to new flag variable

Replace EXTRA_CFLAGS with ccflags-y.

Signed-off-by: matt mooney <mfm@muteddisk.com>
Acked-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>

drivers/misc/cb710/Makefile

@@ -1,6 +1,4 @@
-ifeq ($(CONFIG_CB710_DEBUG),y)
-	EXTRA_CFLAGS		+= -DDEBUG
-endif
+ccflags-$(CONFIG_CB710_DEBUG)	:= -DDEBUG
 
 obj-$(CONFIG_CB710_CORE)	+= cb710.o