staging: exfat: remove two unused functions

Fix sparse warnings:

drivers/staging/exfat/exfat_core.c:2045:4: warning: symbol 'calc_checksum_1byte' was not declared. Should it be static?
drivers/staging/exfat/exfat_core.c:2080:5: warning: symbol 'calc_checksum_4byte' was not declared. Should it be static?

The two functions has no caller in tree, so remove it.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20191114140348.46088-1-yuehaibing@huawei.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/exfat/exfat_core.c

@@ -2042,17 +2042,6 @@ static s32 exfat_calc_num_entries(struct uni_name_t *p_uniname)
 	return (len - 1) / 15 + 3;
 }
 
-u8 calc_checksum_1byte(void *data, s32 len, u8 chksum)
-{
-	int i;
-	u8 *c = (u8 *)data;
-
-	for (i = 0; i < len; i++, c++)
-		chksum = (((chksum & 1) << 7) | ((chksum & 0xFE) >> 1)) + *c;
-
-	return chksum;
-}
-
 u16 calc_checksum_2byte(void *data, s32 len, u16 chksum, s32 type)
 {
 	int i;
@@ -2077,30 +2066,6 @@ u16 calc_checksum_2byte(void *data, s32 len, u16 chksum, s32 type)
 	return chksum;
 }
 
-u32 calc_checksum_4byte(void *data, s32 len, u32 chksum, s32 type)
-{
-	int i;
-	u8 *c = (u8 *)data;
-
-	switch (type) {
-	case CS_PBR_SECTOR:
-		for (i = 0; i < len; i++, c++) {
-			if ((i == 106) || (i == 107) || (i == 112))
-				continue;
-			chksum = (((chksum & 1) << 31) |
-				  ((chksum & 0xFFFFFFFE) >> 1)) + (u32)*c;
-		}
-		break;
-	default
-			:
-		for (i = 0; i < len; i++, c++)
-			chksum = (((chksum & 1) << 31) |
-				  ((chksum & 0xFFFFFFFE) >> 1)) + (u32)*c;
-	}
-
-	return chksum;
-}
-
 /*
  *  Name Resolution Functions
  */