Initialize the remaining size on memory-space aware allocators.

src/initialize_allocator.c

@@ -78,6 +78,7 @@ void initialize_allocator(allocator_t *allocator) {
     allocator->border_ptr = NULL;
 #else
     allocator->border_ptr = starting_address;
+    allocator->remaining_size = size;
 #endif /* WITH_MEMORY_SPACE_AWARENESS */
 
     /* Custom number of fixed lists and their initialization