nvme.i: fixup typo in nvme:discover

The check for existing controller is inverted.

Signed-off-by: Hannes Reinecke <hare@suse.de>

Author: hreinecke

libnvme/nvme.i

@@ -831,7 +831,7 @@ struct nvme_ns {
 		};
 
 		dev = nvme_ctrl_get_name($self);
-		if (dev) {
+		if (!dev) {
 			discover_err = 1;
 			return NULL;
 		}