add OsmoHLR manual, OsmoHLR VTY reference

Change-Id: Ieb6a362a26a7e65199f68f5cd32d9b6b0e5d0fbf
diff --git a/doc/manuals/vty/hlr_vty_additions.xml b/doc/manuals/vty/hlr_vty_additions.xml
new file mode 100644
index 0000000..a4c675e
--- /dev/null
+++ b/doc/manuals/vty/hlr_vty_additions.xml
@@ -0,0 +1,2 @@
+<vtydoc xmlns='urn:osmocom:xml:libosmocore:vty:doc:1.0'>
+</vtydoc>