Check the return value of catta_simple_poll_get().

[meshlink] / catta

diff --git a/catta b/catta
index bb142eb202fda78982305d8aeffc4ae5c16ab1ae..070b95d769cbcbdf0113437a0db92777765474ea 160000 (submodule)
--- a/catta
+++ b/catta
@@ -1 +1 @@
-Subproject commit bb142eb202fda78982305d8aeffc4ae5c16ab1ae
+Subproject commit 070b95d769cbcbdf0113437a0db92777765474ea