rpi4/fdt: Move dtb_size() function to fdt_wrappers.h

Getting the actual size of a DTB blob is useful beyond the Raspberry Pi
port, so let's move this helper to a common header.

Change-Id: Ia5be46e9353ca859a1e5ad9e3c057a322dfe22e2
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
2 files changed