docs: Fix some HTML that leaked into the markdown
@@ -173,7 +173,7 @@ Does a structure contain a member?
==
Some platforms have different standard structures. Here's how one
-would check if a struct called `mystruct` from header `myheader.h</hh>
+would check if a struct called `mystruct` from header `myheader.h`
contains a member called `some_member`.
```meson
