tests: require login for AFP smoke test

Open the libncp connection with login_necessary set to true.

ncpfs/libncp does not block individual NCP endpoints here. The problem was that ncp_initialize(..., 0, ...) deliberately clears the user name even when -S/-U/-P were supplied, leaving the connection unauthenticated. mars_nwe then rejects directory-handle allocation for non-login paths with Invalid Path before the AFP NCP 0x23/0x0c request is ever sent.

The AFP Entry ID smoke test needs normal file-service path access in order to allocate or use a directory handle before issuing the AFP request. Require a logged-in connection, while still allowing no-password test users via libncp's existing -n option.

This changes only the Linux smoke test; server AFP protocol behavior is unchanged.

tests/linux/afp_entry_id_smoke.c

@@ -177,9 +177,17 @@ int main(int argc, char **argv)
         return 2;
     }
 
-    conn = ncp_initialize(&argc, argv, 0, &init_err);
+    /*
+     * The smoke test needs normal file-service path access before it can send
+     * AFP 0x0c: it has to allocate/use a directory handle for the supplied
+     * VOL:PATH.  ncp_initialize(..., 0, ...) intentionally clears the user
+     * name even if -U/-P were supplied, so mars_nwe treats the connection as
+     * unauthenticated and rejects non-login paths before the AFP request is
+     * reached.  Require a login here; no-password users can still use -n.
+     */
+    conn = ncp_initialize(&argc, argv, 1, &init_err);
     if (!conn) {
-        fprintf(stderr, "ncp_initialize failed: %ld\n", init_err);
+        fprintf(stderr, "ncp_initialize/login failed: %ld\n", init_err);
         usage(argv[0]);
         return 2;
     }