FIX: do not merge

Author: ldorau

src/provider/provider_coarse.c

@@ -813,8 +813,8 @@ coarse_add_upstream_block(coarse_memory_provider_t *coarse_provider, void *addr,
     }
 
     // check if the new upstream block can be merged with its neighbours
-    alloc_node = upstream_block_merge_with_prev(coarse_provider, alloc_node);
-    alloc_node = upstream_block_merge_with_next(coarse_provider, alloc_node);
+    // alloc_node = upstream_block_merge_with_prev(coarse_provider, alloc_node);
+    // alloc_node = upstream_block_merge_with_next(coarse_provider, alloc_node);
 
     new_block->used = true;
     coarse_provider->alloc_size += size;