Stop library before checking for mem leaks

With the new init framework resources aren't released until the process
exits. This means checking for mem leaks before that point finds a lot of
things! We should explicitly close down the library if we're checking for
mem leaks.
Reviewed-by: NRich Salz <rsalz@openssl.org>

crypto/mem_dbg.c

@@ -639,6 +639,9 @@ int CRYPTO_mem_leaks(BIO *b)
     if (mh == NULL && amih == NULL)
         return 1;
 
+    /* Ensure all resources are released */
+    OPENSSL_INIT_library_stop();
+
     CRYPTO_mem_ctrl(CRYPTO_MEM_CHECK_DISABLE);
 
     ml.bio = b;