host_timer(): fixed wrong cut-off by "quick connect pool".

We were not comparing the right values: the "quick connect pool" reflects
how many outstanding connection attempts we can have on top of the established
connections, not the total amount of "connected + attempts".

Hence host_timer() could bail out early, even though the configured minimum
connection count was not reached!
 node_qrt_changed(): assert the "normal node" mode is no longer supported.
Fixed compilation warnings with the clang C compiler.