To make software license auditing simpler, use SPDX[0] license
identifiers instead of duplicating the license text in every file.

NOTE: Files that have been imported by FreeBSD have not been modified.

[0]: https://spdx.org/

Change-Id: I80a00e1f641b8cc075ca5a95b10607ed9ed8761a
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>

This patch adds a CoT based on the Trusted Board Boot Requirements
document*. The CoT consists of an array of authentication image
descriptors indexed by the image identifiers.

A new header file with TBBR image identifiers has been added.
Platforms that use the TBBR (i.e. ARM platforms) may reuse these
definitions as part of their platform porting.

PLATFORM PORT - IMPORTANT:

Default image IDs have been removed from the platform common
definitions file (common_def.h). As a consequence, platforms that
used those common definitons must now either include the IDs
provided by the TBBR header file or define their own IDs.

*The NVCounter authentication method has not been implemented yet.

Change-Id: I7c4d591863ef53bb0cd4ce6c52a60b06fa0102d5