mtd: docg3 fix missing bitreverse lib

Fix missing dependency which can cause a build error such
as: ERROR: "byte_rev_table" [drivers/mtd/devices/docg3.ko]
undefined!
Reported-by: NRandy Dunlap <rdunlap@infradead.org>
Acked-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NRobert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

drivers/mtd/devices/Kconfig

@@ -272,6 +272,7 @@ config MTD_DOCG3
 	tristate "M-Systems Disk-On-Chip G3"
 	select BCH
 	select BCH_CONST_PARAMS
+	select BITREVERSE
 	---help---
 	  This provides an MTD device driver for the M-Systems DiskOnChip
 	  G3 devices.