lib: correct 842 decompress for 32 bit

Avoid 64 bit mod operation, which won't work on 32 bit systems.
Simple subtraction can be used instead in this case.

Reported-By: Fengguang Wu <[email protected]>
Signed-off-by: Dan Streetman <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>

lib/842/842_decompress.c

@@ -185,7 +185,7 @@ static int __do_index(struct sw842_param *p, u8 size, u8 bits, u64 fsize)
  /* this is where the current fifo is */
  u64 section = round_down(total, fsize);
  /* the current pos in the fifo */
- u64 pos = total % fsize;
+ u64 pos = total - section;
 
  /* if the offset is past/at the pos, we need to
  * go back to the last fifo section