linux-boundary: Add recipe for Boundary Devices kernel

This provides a kernel for use with SabreLITE and Nitrogen6X boards.

Change-Id: I02477254b2986ffb05b81b264121527238800fcd
Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
imx6qsabrelite: Add Boundary Devices SabreLITE machine definition

This adds the Boundary Devices SabreLITE machine which were maintained
in meta-fsl-arm. We did this change as the support of the board is not
done by Freescale officially and the kernel with better support is the
one done by Boundary Devices which we now have available.

Change-Id: Ie040b38e23885fa164bb4cd25d8c4b0b00471e5c
Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>
nitrogen6x: Change machine to use linux-boundary kernel

Change-Id: Ie815cf603657385e3220640c7773f2d3eaee7c8b
Signed-off-by: Otavio Salvador <otavio@ossystems.com.br>