MIPS: Netlogic: DTS file for XLP boards

Add a basic DTS file netlogic/dts/nlm_xlp.dts which contains
memory, i2c devices, NOR flash and command line arguments.

Signed-off-by: Ganesan Ramalingam <ganesanr@broadcom.com>
Signed-off-by: Jayachandran C <jayachandranc@netlogicmicro.com>
Patchwork: http://patchwork.linux-mips.org/patch/4100/


Signed-off-by: John Crispin <blogic@openwrt.org>