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/taishan.h b/include/configs/taishan.h
index ba42192..81133bb 100644
--- a/include/configs/taishan.h
+++ b/include/configs/taishan.h
@@ -89,7 +89,7 @@
  * FLASH related
  *----------------------------------------------------------------------*/
 #define CFG_FLASH_CFI
-#define CFG_FLASH_CFI_DRIVER
+#define CONFIG_FLASH_CFI_DRIVER
 #define CFG_FLASH_EMPTY_INFO		/* print 'E' for empty sector on flinfo */
 #define CFG_FLASH_USE_BUFFER_WRITE 1	/* use buffered writes (20x faster)	*/