dataflash: Move CONFIG_HAS_DATAFLASH to Makefile

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
diff --git a/drivers/mtd/Makefile b/drivers/mtd/Makefile
index 952e919..ff932a1 100644
--- a/drivers/mtd/Makefile
+++ b/drivers/mtd/Makefile
@@ -23,17 +23,17 @@
 
 include $(TOPDIR)/config.mk
 
-LIB 	:= $(obj)libmtd.a
+LIB	:= $(obj)libmtd.a
 
 COBJS-y += at45.o
 COBJS-y += cfi_flash.o
-COBJS-y += dataflash.o
+COBJS-$(CONFIG_HAS_DATAFLASH) += dataflash.o
 COBJS-y += mw_eeprom.o
 COBJS-$(CONFIG_FLASH_CFI_LEGACY) += jedec_flash.o
 
 COBJS	:= $(COBJS-y)
-SRCS 	:= $(COBJS:.o=.c)
-OBJS 	:= $(addprefix $(obj),$(COBJS))
+SRCS	:= $(COBJS:.o=.c)
+OBJS	:= $(addprefix $(obj),$(COBJS))
 
 all:	$(LIB)