Fix exit status of lxc controller

The LXC controller main() method initialized 'rc' to 1
rather than '-1'. In the cleanup path it will print any
error to stderr, if-and-only-if rc < 0. Hence the incorrect
initialization caused errors to be lost.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>

src/lxc/lxc_controller.c

@@ -2230,7 +2230,7 @@ cleanup:
 int main(int argc, char *argv[])
 {
     pid_t pid;
-    int rc = 1;
+    int rc = -1;
     char *name = NULL;
     size_t nveths = 0;
     char **veths = NULL;