Add AES_PSA_INIT() to thread test case

Tests were failing when PSA was being used in ctr_drbg_seed() as PSA was
not initialised.

Signed-off-by: Paul Elliott <paul.elliott@arm.com>

tests/suites/test_suite_ctr_drbg.function

@@ -356,6 +356,8 @@ void ctr_drbg_threads(data_t *expected_result, int reseed, int arg_thread_count)
     /* Based on the size of MBEDTLS_CTR_DRBG_ENTROPY_LEN for SHA512. */
     const size_t entropy_len = 48;
 
+    AES_PSA_INIT();
+
     TEST_CALLOC(threads, sizeof(pthread_t) * thread_count);
     memset(out, 0, sizeof(out));
 
@@ -408,6 +410,8 @@ exit:
     mbedtls_ctr_drbg_free(&ctx);
     mbedtls_free(entropy);
     mbedtls_free(threads);
+
+    AES_PSA_DONE();
 }
 /* END_CASE */