drivers/mtd: Move conditional compilation to Makefile

rename CFG_FLASH_CFI_DRIVER to CONFIG_FLASH_CFI_DRIVER

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
diff --git a/include/configs/eXalion.h b/include/configs/eXalion.h
index f8e2c88..6ba0d3f 100644
--- a/include/configs/eXalion.h
+++ b/include/configs/eXalion.h
@@ -170,7 +170,7 @@
  */
 
 #define CFG_FLASH_CFI		1	/* Flash is CFI conformant		*/
-#define CFG_FLASH_CFI_DRIVER	1	/* Use the common driver		*/
+#define CONFIG_FLASH_CFI_DRIVER	1	/* Use the common driver		*/
 #define CFG_MAX_FLASH_SECT	64	/* max number of sectors on one chip	*/
 #define CFG_MAX_FLASH_BANKS	1	/* max number of memory banks		*/
 #define CFG_FLASH_INCREMENT	0	/* there is only one bank		*/