test_suite_[pkparse/rsa]: move RSA private key parsing tests

Signed-off-by: Valerio Setti <valerio.setti@nordicsemi.no>
diff --git a/tests/suites/test_suite_rsa.function b/tests/suites/test_suite_rsa.function
index 62f593e..4fe15dd 100644
--- a/tests/suites/test_suite_rsa.function
+++ b/tests/suites/test_suite_rsa.function
@@ -1373,6 +1373,19 @@
 /* END_CASE */
 
 /* BEGIN_CASE */
+void rsa_parse_pkcs1_key(data_t *input, int exp_ret_val)
+{
+    mbedtls_rsa_context rsa_ctx;
+    mbedtls_rsa_init(&rsa_ctx);
+
+    TEST_EQUAL(mbedtls_rsa_key_parse(&rsa_ctx, input->x, input->len), exp_ret_val);
+
+exit:
+    mbedtls_rsa_free(&rsa_ctx);
+}
+/* END_CASE */
+
+/* BEGIN_CASE */
 void rsa_parse_write_pkcs1_key(int is_public, data_t *input)
 {
     mbedtls_rsa_context rsa_ctx;