mtd: Fix misspelled function parameter 'section'

mtd: Fix misspelled function parameter 'section'

Fixes the following W=1 kernel build warning(s):

 drivers/mtd/mtdcore.c:1592: warning: Function parameter or member 'section' not described in 'mtd_ooblayout_find_eccregion'
 drivers/mtd/mtdcore.c:1592: warning: Excess function parameter 'sectionp' description in 'mtd_ooblayout_find_eccregion'

Cc: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Vignesh Raghavendra <vigneshr@ti.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: linux-mtd@lists.infradead.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Alexander Dahl <ada@thorsis.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20201109182206.3037326-6-lee.jones@linaro.org