Add certificate policy of type any policy id

Add a function for getting the certificate policy. Currently only
"Any Policy" is supported.
diff --git a/tests/suites/test_suite_oid.data b/tests/suites/test_suite_oid.data
new file mode 100644
index 0000000..759a010
--- /dev/null
+++ b/tests/suites/test_suite_oid.data
@@ -0,0 +1,8 @@
+OID get Any Policy certificate policy
+oid_get_certificate_policies:"551D2000":"Any Policy"
+
+OID get certificate policy invalid oid
+oid_get_certificate_policies:"5533445566":""
+
+OID get certificate policy wrong oid - id-ce-authorityKeyIdentifier
+oid_get_certificate_policies:"551D23":""