MIPS: Use early_init_fdt_reserve_self to protect DTB location

MIPS: Use early_init_fdt_reserve_self to protect DTB location

early_init_fdt_reserve_self is used to tell the boot memory allocator
that a memory is occupied by the DTB, so add it in the MIPS init code to
ensure information about the DTB is added to the boot memory array.

Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14610/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>