explicit init

Reviewed-by: NMatt Caswell <matt@openssl.org>
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/1301)

crypto/engine/eng_openssl.c

@@ -264,7 +264,7 @@ static void test_r4_40_cipher_destroy(void)
 }
 static int test_cipher_nids(const int **nids)
 {
-    static int cipher_nids[4] = { 0, 0, 0 };
+    static int cipher_nids[4] = { 0, 0, 0, 0 };
     static int pos = 0;
     static int init = 0;