Add a poll callback to channels.

[meshlink] / src / utcp

diff --git a/src/utcp b/src/utcp
index d5888c10a181d6247e407f480524d36be6319b3e..5d4cf9d0eb85c7322298a2a0526132197e3bf633 160000 (submodule)
--- a/src/utcp
+++ b/src/utcp
@@ -1 +1 @@
-Subproject commit d5888c10a181d6247e407f480524d36be6319b3e
+Subproject commit 5d4cf9d0eb85c7322298a2a0526132197e3bf633