test: fix watcher_cross_stop
test: fix watcher_cross_stop

It's possible that recv_cb_called is bigger than the number of sockets,
because if all sends succeed the recv callback is called twice: once
with the actual data, and another time with 0.

unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso