mtd: rawnand: pl353: Fix kernel doc

Both the "chip" kernel doc member and description are wrong. This field
is called "chips" and describes the list of NAND chips connected to the
controller.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202312102130.geZ4dqyN-lkp@intel.com/
Fixes: 08d8c621

 ("mtd: rawnand: pl353: Add support for the ARM PL353 SMC NAND controller")
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20231211150524.108803-1-miquel.raynal@bootlin.com