cert_create: Remove some unused header files inclusions

The chain of trust definitions are only needed in the part of the code
dealing with the TBBR CoT (tbbr/* files).

Change-Id: I6f9a86bba4a2d16313b6842a3ec85b7c951074bc
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>
3 files changed