Restore module loading

The module loading feature got broken a while ago, so restore it, but
have it a bit more explicit this time around.

Reviewed-by: Stephen Henson <steve@openssl.org>

apps/pkeyparam.c

@@ -118,6 +118,9 @@ int pkeyparam_main(int argc, char **argv)
     argc = opt_num_rest();
     argv = opt_rest();
 
+    if (!app_load_modules(NULL))
+        goto end;
+
     in = bio_open_default(infile, "r");
     if (in == NULL)
         goto end;