Core: Update the code related with request message type

The patch inlcudes the following changes:
 -Create message with type instead of PSA_IPC_CALL in
  tfm_svcall_psa_call();
 -Change the condition to check whether message handle refers to a
  request message instead of PSA_IPC_CALL;
 -Move the request message logic into default block in
  tfm_svcall_psa_reply().

Change-Id: I0c59b5f55c4a46feb05c674d5cb3bce666779171
Signed-off-by: Summer Qin <summer.qin@arm.com>