mtd: nand: vf610_nfc: remove unused function

The function count_written_bits has been replaced by the generic
nand_check_erased_ecc_chunk() function with commit 48c25cf4
("mtd: nand: vf610_nfc: use nand_check_erased_ecc_chunk() helper").
Remove the unused function.
Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>

drivers/mtd/nand/vf610_nfc.c

@@ -511,21 +511,6 @@ static void vf610_nfc_select_chip(struct mtd_info *mtd, int chip)
 	vf610_nfc_write(nfc, NFC_ROW_ADDR, tmp);
 }
 
-/* Count the number of 0's in buff up to max_bits */
-static inline int count_written_bits(uint8_t *buff, int size, int max_bits)
-{
-	uint32_t *buff32 = (uint32_t *)buff;
-	int k, written_bits = 0;
-
-	for (k = 0; k < (size / 4); k++) {
-		written_bits += hweight32(~buff32[k]);
-		if (unlikely(written_bits > max_bits))
-			break;
-	}
-
-	return written_bits;
-}
-
 static inline int vf610_nfc_correct_data(struct mtd_info *mtd, uint8_t *dat,
 					 uint8_t *oob, int page)
 {