Drivers (both built-in and external) need to declare their context
structures in a way such that they are accessible by the
to-be-autogenerated crypto_driver_contexts.h file. That file lives in
include/psa, which means all builtin driver context structure
declarations also need to live in include/psa.
Signed-off-by: Steven Cooreman <steven.cooreman@silabs.com>