docs: Remove XML-style comments from documentation strings

gtk-doc doesn’t support them any more since it was ported to Markdown,
so they end up appearing in the generated documentation, which isn’t
great.

Mostly, they were used to split up things invisibly, which we can do in
other ways.

Signed-off-by: Philip Withnall <withnall@endlessm.com>
Reviewed-by: nobody

gio/gsocketaddressenumerator.h

@@ -38,7 +38,7 @@ G_BEGIN_DECLS
  * GSocketAddressEnumerator:
  *
  * Enumerator type for objects that contain or generate
- * #GSocketAddress<!-- -->es.
+ * #GSocketAddress instances.
  */
 typedef struct _GSocketAddressEnumeratorClass GSocketAddressEnumeratorClass;