avcodec/bonk: step cannot become 0 without overflowing which is undefined

also the original reference code does not contain a 0 check

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libavcodec/bonk.c

@@ -203,8 +203,6 @@ static int intlist_read(BonkContext *s, int *buf, int entries, int base_2_part)
         }
 
         if (step < 256) {
-            if (step == 0)
-                return AVERROR_INVALIDDATA;
             step = 65536 / step;
             dominant = !dominant;
         }