ecore_con: Force unsigned to unsigned comparison

ecore_con: Force unsigned to unsigned comparison

num was changed to size_t which makes it unsigned while count is a normal
(signed) int. Comparing them does not always work as expected but in this
case we already checked if count is < 0 before and would have returned if
that would be true. Thus we can safely cast count to unsigned here as it
will be greater 0 anyway.