Move num ops update to only point where work can be done.

Signed-off-by: Paul Elliott <paul.elliott@arm.com>
diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index e10c34c..d458b02 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -3287,11 +3287,12 @@
     status = psa_driver_wrapper_sign_hash_complete(operation, signature,
                                                    signature_size,
                                                    signature_length);
-exit:
 
     /* Update ops count with work done. */
     operation->num_ops = psa_driver_wrapper_sign_hash_get_num_ops(operation);
 
+exit:
+
     psa_wipe_output_buffer(signature, status, signature_size,
                            *signature_length);
 
@@ -3418,12 +3419,12 @@
 
     status = psa_driver_wrapper_verify_hash_complete(operation);
 
-exit:
-
     /* Update ops count with work done. */
     operation->num_ops = psa_driver_wrapper_verify_hash_get_num_ops(
         operation);
 
+exit:
+
     if (status != PSA_OPERATION_INCOMPLETE) {
         if (status != PSA_SUCCESS) {
             operation->error_occurred = 1;