Add tests for the key agreement driver wrapper to test_suite_psa_crypto_driver_wrappers

Signed-off-by: Aditya Deshpande <aditya.deshpande@arm.com>
diff --git a/tests/include/test/drivers/key_agreement.h b/tests/include/test/drivers/key_agreement.h
index 634cbac..ec65159 100644
--- a/tests/include/test/drivers/key_agreement.h
+++ b/tests/include/test/drivers/key_agreement.h
@@ -45,6 +45,9 @@
     return( v );
 }
 
+extern mbedtls_test_driver_key_agreement_hooks_t
+    mbedtls_test_driver_key_agreement_hooks;
+
 psa_status_t mbedtls_test_transparent_key_agreement(
     const psa_key_attributes_t *attributes,
     const uint8_t *key_buffer,