confd: Simplify enabling features in YANG models

If a extra infix feature  require features to be added to an already
loaded module. Instead of have the exact module definition in multiple
places (with date), this will allow a much more flexible sytax:

MODULES=(
	"infix-interfaces -e containers"
)

This require that the infix-interfaces is loaded *before* this file
is run.

src/confd/yang/confd.inc

@@ -1,5 +1,4 @@
 # -*- sh -*-
-# REMEMBER TO UPDATE infix-interfaces ALSO IN containers.inc
 
 MODULES=(
 	"ietf-system@2014-08-06.yang -e authentication -e local-users -e ntp -e ntp-udp-port -e timezone-name"

src/confd/yang/containers.inc

@@ -1,6 +1,5 @@
 # -*- sh -*-
-# REMEMBER TO UPDATE infix-interfaces ALSO IN confd.inc
 MODULES=(
-    "infix-interfaces@2025-01-09.yang -e vlan-filtering -e containers"
+    "infix-interfaces -e containers"
     "infix-containers@2025-05-14.yang"
 )