Fix typos.
diff --git a/src/hb-blob.h b/src/hb-blob.h
index ef3fc98..53682d3 100644
--- a/src/hb-blob.h
+++ b/src/hb-blob.h
@@ -44,7 +44,7 @@
  *   any such possibility, MODE_DUPLICATE should be used
  *   such that HarfBuzz makes a copy immediately,
  *
- * - Use MODE_READONLY otherse, unless you really really
+ * - Use MODE_READONLY otherwise, unless you really really
  *   really know what you are doing,
  *
  * - MODE_WRITABLE is appropriate if you really made a