[OE-core] [backport][dizzy][daisy] utils.bbclass: fix create_cmdline_wrapper

[Viguera, Javier]

Hi Saul,

> Added to my pending branch for Daisy, I am doing a sweep of the list
> now
> for a 1.6.3 build later this week.
> 
> Sau!

I see this patch didn't make it to the just-built 'yocto-1.6.3.rc1'.

Is there any problem with it? It's included in master and Dizzy but if it needs rework for Daisy I can do that.

-
Thanks

Javier Viguera