mtd: nand: rename NAND_USE_FLASH_BBT

Recall the recently added prefix requirements:
 * "NAND_" for flags in nand.h, used in nand_chip.options
 * "NAND_BBT_" for flags in bbm.h, used in nand_chip.bbt_options
        or in nand_bbt_descr.options

Thus, I am changing NAND_USE_FLASH_BBT to NAND_BBT_USE_FLASH.

Again, this flag is found in bbm.h and so should NOT be used in the
"nand_chip.options" field.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/include/linux/mtd/bbm.h b/include/linux/mtd/bbm.h
index 7929514..ff18c08 100644
--- a/include/linux/mtd/bbm.h
+++ b/include/linux/mtd/bbm.h
@@ -104,7 +104,7 @@
  * Use a flash based bad block table. By default, OOB identifier is saved in
  * OOB area. This option is passed to the default bad block table function.
  */
-#define NAND_USE_FLASH_BBT	0x00040000
+#define NAND_BBT_USE_FLASH	0x00040000
 /* Do not store flash based bad block table in OOB area; store it in-band */
 #define NAND_BBT_NO_OOB		0x00080000