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/MPC8541CDS.h b/include/configs/MPC8541CDS.h
index a64565d..d948d76 100644
--- a/include/configs/MPC8541CDS.h
+++ b/include/configs/MPC8541CDS.h
@@ -154,7 +154,7 @@
 
 #define CFG_MONITOR_BASE	TEXT_BASE	/* start of monitor */
 
-#define CFG_FLASH_CFI_DRIVER
+#define CONFIG_FLASH_CFI_DRIVER
 #define CFG_FLASH_CFI
 #define CFG_FLASH_EMPTY_INFO