Change ipsec feature node names

ipsec4-output and ipsec6-output were conflicting with ipsec
interface names ("ipsec<id>") and vnet/interface.c autogenerated
output node ("<ifname>-output").

Changing feature names seems to be the less invasive option.
This patch also changes "input" feature names for consistency.

Change-Id: I4ba10d07e9ba09df20aa2500104252b06b55f8f7
Signed-off-by: Pierre Pfister <ppfister@cisco.com>
diff --git a/src/vnet/ipsec/ipsec_if_in.c b/src/vnet/ipsec/ipsec_if_in.c
index a9aab82..1dbd127 100644
--- a/src/vnet/ipsec/ipsec_if_in.c
+++ b/src/vnet/ipsec/ipsec_if_in.c
@@ -230,7 +230,7 @@
   .n_errors = ARRAY_LEN(ipsec_if_input_error_strings),
   .error_strings = ipsec_if_input_error_strings,
 
-  .sibling_of = "ipsec4-input",
+  .sibling_of = "ipsec4-input-feature",
 };
 /* *INDENT-ON* */