[manual] mkdir second form is not described

[John W. Eaton]

On 14-Sep-2008, Thomas Weber wrote:

| On Sat, Sep 13, 2008 at 01:02:12PM +0200, Francesco Potorti` wrote:
| > In Octave 3.0.1, both the halp string and the manual do not describe
| > what the second form of mkdir (the one with two argument) does.
| 
| Patch attached.

I applied it.

Thanks,

jwe