* setting APPEND in the image file overwrites
the APPEND from boot-directdisk.bbclass in edison, which
creates the syslinux.cfg without "root=" stanza
* for dora we do not use syslinux or the image-directdisk
so revert this paticular changes
Fixes: SYS#373
* use seperate defconfig, because of option changed from 2.6.39 to 3.10
* use python magic to switch between linux and linux-sysmocom
* add sysmocom-bsc to compatible machines for linux-sysmocom
* add new confiugration parameters for syslinux
This sanity check is included in the used bbclass directly and to
support both Edison and master we will need to remove the custom
python code due a change in indention in the python code.
Henning Heinold
Holger Hans Peter Freyther