tools: kwbimage: Update comments describing kwbimage v1 structures

These structures are relevant for several other platforms, mention them
all.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Marek Behún <marek.behun@nic.cz>
Reviewed-by: Stefan Roese <sr@denx.de>
2 files changed