[oe] Amend recipes which do not contain a (new) target machine in COMPATIBLE_MACHINE

[Hauser, Wolfgang (external)]

>COMPATIBLE_MACHINE is a regular expression, so you need to make sure
the 
>syntax is not broken when you append to it. In the case of
linux-omap-psp, you 
>can try adding "|mymachine"...

Well, COMPATIBLE_MACHINE_append_pn-linux-omap-psp = "|mymachine" is the
working one.

Thanks to all, helped me getting forward.