Introduce helpers for computing dtb size

This patch introduce fdt_node_len and fdt_prop_len to help for computing
memory requirement when operating dtb.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Introduce setup_dtb_prop to make code clear

This patch introduces setup_dtb_prop(), which is used for dtb operations. The
code is extracted from zImage_arm_load, and this patch makes memory grown
computation more accurate.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Pass initrd position by dtb

This patch append the position of initrd to dtb when loading arm kernel
and initrd without using atag.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Acked-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Simon Horman <horms@verge.net.au>