feat(dice): add typedefs from the Open DICE repo

The DPE implementation in RSS is aligned with the
Open Profile for DICE specification:
https://pigweed.googlesource.com/open-dice/

Type definitions are needed to specify the input
values for the DPE service. Instead of mandating to
clone the entire open-dice repo, the following file
is copied from the repository:
https://pigweed.googlesource.com/open-dice/+/refs/heads/main/include/dice/dice.h
Git SHA of the source version: cf549422e39da872d64993be944099ac62ba22a9

This is external code, with Apache 2.0 license, therefore
the license.rst is updated accordingly and a copy of this
license is also added.

Signed-off-by: Tamas Ban <tamas.ban@arm.com>
Signed-off-by: David Vincze <david.vincze@arm.com>
Change-Id: Ie84b8483034819d1143fe0ec812e66514ac7d4cb
4 files changed