mtd: docg3: fix kernel-doc warnings

Fix kernel-doc warnings in docg3.h to avoid build warnings:

Warning: ../drivers/mtd/devices/docg3.h:276 bad line:
Warning: drivers/mtd/devices/docg3.h:299 struct member 'max_block' not
 described in 'docg3'

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

Author: rddunlap

drivers/mtd/devices/docg3.h

@@ -274,11 +274,11 @@ struct docg3_cascade {
  * @cascade: the cascade this device belongs to
  * @device_id: number of the cascaded DoCG3 device (0, 1, 2 or 3)
  * @if_cfg: if true, reads are on 16bits, else reads are on 8bits
-
  * @reliable: if 0, docg3 in normal mode, if 1 docg3 in fast mode, if 2 in
  *            reliable mode
  *            Fast mode implies more errors than normal mode.
  *            Reliable mode implies that page 2*n and 2*n+1 are clones.
+ * @max_block: maximum block number for this device
  * @bbt: bad block table cache
  * @oob_write_ofs: offset of the MTD where this OOB should belong (ie. in next
  *                 page_write)