Attest: Implement get token size API

Extend the attestation API with the implementation of
psa_initial_attest_get_token_size() function. It is
meant for retrieving the exact size of the initial
attestation token, but current version just returns
a hard coded value.

Replacement of handwritten veneers to the auto-generated
veneers.

Change-Id: Ibc91c6cdaeecec59c4e1f18576783cb55723e9ec
Signed-off-by: Tamas Ban <tamas.ban@arm.com>
diff --git a/interface/include/tfm_veneers.h b/interface/include/tfm_veneers.h
index 1e03e08..c238b35 100644
--- a/interface/include/tfm_veneers.h
+++ b/interface/include/tfm_veneers.h
@@ -52,6 +52,7 @@
 
 /******** TFM_SP_INITIAL_ATTESTATION ********/
 psa_status_t tfm_initial_attest_get_token_veneer(struct psa_invec *in_vec, size_t in_len, struct psa_outvec *out_vec, size_t out_len);
+psa_status_t tfm_initial_attest_get_token_size_veneer(struct psa_invec *in_vec, size_t in_len, struct psa_outvec *out_vec, size_t out_len);
 
 #ifdef TFM_PARTITION_TEST_CORE
 /******** TFM_SP_CORE_TEST ********/