mtd: nand: remove unused blockmask variable

This patch fix the following build warning:
drivers/mtd/nand/nand_base.c:2671:30: attention : variable ‘blockmask’ set but not used [-Wunused-but-set-variable]

Fixes: 0b4773f ("mtd: nand: Drop unused cached programming support")
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>

drivers/mtd/nand/nand_base.c

@@ -2668,7 +2668,7 @@ static uint8_t *nand_fill_oob(struct mtd_info *mtd, uint8_t *oob, size_t len,
 static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
 			     struct mtd_oob_ops *ops)
 {
-	int chipnr, realpage, page, blockmask, column;
+	int chipnr, realpage, page, column;
 	struct nand_chip *chip = mtd_to_nand(mtd);
 	uint32_t writelen = ops->len;
 
@@ -2704,7 +2704,6 @@ static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
 
 	realpage = (int)(to >> chip->page_shift);
 	page = realpage & chip->pagemask;
-	blockmask = (1 << (chip->phys_erase_shift - chip->page_shift)) - 1;
 
 	/* Invalidate the page cache, when we write to the cached page */
 	if (to <= ((loff_t)chip->pagebuf << chip->page_shift) &&