CMin: don't add to map if it's the initial value (uninteresting) (#1078)

libafl/src/corpus/minimizer.rs

@@ -142,6 +142,7 @@ where
             // Store coverage, mapping coverage map indices to hit counts (if present) and the
             // associated seeds for the map indices with those hit counts.
             for (i, e) in obs.as_iter().copied().enumerate() {
+                if e != obs.initial() {
                     cov_map
                         .entry(i)
                         .or_insert_with(HashMap::new)
@@ -149,6 +150,7 @@ where
                         .or_insert_with(HashSet::new)
                         .insert(seed_expr.clone());
                 }
+            }
 
             // Keep track of that seed's index and weight
             seed_exprs.insert(seed_expr, (idx, weight));