armh: update warning in 50-sshd-root

It basically reads the same but was referring to a neighbour
script that has been moved to a separate deflogin feature
during heavy refactoring of initial implementation draft.

features.in/armh/rootfs/image-scripts.d/50-sshd-root

@@ -1,6 +1,6 @@
 #!/bin/sh
 # poor man's root switch
-# NB: 50-users creates predefined users
+# NB: use/deflogin might have been used to create predefined users
 
 cat >> /etc/openssh/sshd_config << EOF
 PermitRootLogin yes