dfu: include MCUboot's bootutil_public.h

This header provides original BOOT_MAX_ALIGN definition.
This definition is used directly on indirectly by the code this
patch modifies.
Let's use it instead of copy from mcuboot.h

Signed-off-by: Andrzej Puzdrowski <andrzej.puzdrowski@nordicsemi.no>
6 files changed