Restore array formatting

Signed-off-by: Ryan Everett <ryan.everett@arm.com>
diff --git a/library/oid.c b/library/oid.c
index 89d133d..a1cf6fc 100644
--- a/library/oid.c
+++ b/library/oid.c
@@ -710,7 +710,7 @@
     {
         NULL_OID_DESCRIPTOR,
         MBEDTLS_CIPHER_NONE,
-    }
+    },
 };
 
 FN_OID_TYPED_FROM_ASN1(oid_cipher_alg_t, cipher_alg, oid_cipher_alg)