Crypto: Check ownership of context

This patch introduces additional checks in the Crypto service
to make sure that a multipart operation context user is consistent
between calls. The same concept is extended to key handles which
are allocated subsequently and can be easily guessed.

Signed-off-by: Antonio de Angelis <antonio.deangelis@arm.com>
Change-Id: I16a9469682f203083a07ec623127fea71fd9f1e6
9 files changed