Fix a comment.
diff --git a/include/jemalloc/internal/arena.h b/include/jemalloc/internal/arena.h
index f972e8b..cb015ee 100644
--- a/include/jemalloc/internal/arena.h
+++ b/include/jemalloc/internal/arena.h
@@ -54,7 +54,7 @@
* Run address (or size) and various flags are stored together. The bit
* layout looks like (assuming 32-bit system):
*
- * ???????? ???????? ???nnnnn nnndulma
+ * ???????? ???????? ???nnnnn nnndumla
*
* ? : Unallocated: Run address for first/last pages, unset for internal
* pages.