doxygen: split VTY configuration in multiple files
diff --git a/include/osmocom/vty/command.h b/include/osmocom/vty/command.h
index c50f256..79d0aec 100644
--- a/include/osmocom/vty/command.h
+++ b/include/osmocom/vty/command.h
@@ -28,7 +28,7 @@
 #include "vector.h"
 #include "vty.h"
 
-/*! \addtogroup vty
+/*! \defgroup command VTY Command
  *  @{
  */
 /*! \file command.h */