ip: reassembly: add documentation

Type: docs
Signed-off-by: Klement Sekera <ksekera@cisco.com>
Change-Id: I23008cde47d8b7a531346eab02902e2ced18742a
diff --git a/docs/developer/corefeatures/index.rst b/docs/developer/corefeatures/index.rst
index adc086e..1012387 100644
--- a/docs/developer/corefeatures/index.rst
+++ b/docs/developer/corefeatures/index.rst
@@ -12,6 +12,7 @@
     punt
     ipsec
     bfd_doc
+    reassembly
     ipfix_doc
     span_doc
     mtu