cgtqmx6: changing preferred kernel assignement type

The assignement of the preferred kernel was changed
so that It is possible do define a different one in
local.conf

Signed-off-by: Raphael Silva <raphael.philipe@ossystems.com.br>
Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
linux-congatec-rt: add initial recipe

Add initial support for 3.10.17-1.0.2 with 3.10.17-rt12 real-time patch.

Signed-off-by: Raphael Silva <raphael.philipe@ossystems.com.br>
Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>