Recent change in d1b287e only fixed the problem for 3-letter words.
We were still displaying error for longer words starting with "ena":
```
nfware> enac
% Command not allowed: enable
nfware> enad
% Command not allowed: enable
nfware> enaena
% Command not allowed: enable
```
If we don't allow "enable" command in user mode, why add it at all?
Signed-off-by: Igor Ryzhov <iryzhov@nfware.com>