MIPS: Netlogic: Move fdt init to plat_mem_setup

At this point early printk is available, so debugging device tree
issues is easier.

Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Patchwork: http://patchwork.linux-mips.org/patch/4460


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