C, recursive alias declarations

Fixes sphinx-doc/sphinx#8141

doc/usage/restructuredtext/domains.rst

@@ -744,6 +744,18 @@ The following directive can be used for this purpose.
 
    .. versionadded:: 3.2
 
+
+   .. rubric:: Options
+
+   .. rst:directive:option:: maxdepth: int
+
+      Insert nested declarations as well, up to the total depth given.
+      Use 0 for infinite depth and 1 for just the mentioned declaration.
+      Defaults to 1.
+
+      .. versionadded:: 3.3
+
+
 .. c:namespace-pop::