mtd: nand_bbt: kill NAND_BBT_SCANALLPAGES

Now that the last user of NAND_BBT_SCANALLPAGES has been removed, let's
kill this peculiar BBT feature flag.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

Documentation/DocBook/mtdnand.tmpl

@@ -1222,8 +1222,6 @@ in this page</entry>
 #define NAND_BBT_VERSION	0x00000100
 /* Create a bbt if none axists */
 #define NAND_BBT_CREATE		0x00000200
-/* Search good / bad pattern through all pages of a block */
-#define NAND_BBT_SCANALLPAGES	0x00000400
 /* Write bbt if neccecary */
 #define NAND_BBT_WRITE		0x00001000
 /* Read and write back block contents when writing bbt */