Platform: Rename device ID to be aligned with PSA SM

Details:
 - Rename device ID to instance ID to be aligned with PSA
   Security Model (PSA SM)
 - Modify dummy implementation to use the hash of attestation
   public key as instance ID
 - Update relevant functions and defines in initial
   attestation service and in its test suite

Change-Id: Icd7f3666b7ee02e4890736441fc4b233987b9979
Signed-off-by: Tamas Ban <tamas.ban@arm.com>
10 files changed