chpst: fix a bug where -U USER was using wrong USER (one from -u USER)

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
fix assorted unused code and wrong format specs found by cppchekc (bug 6716)

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Use unsigned printf/scanf conversion where more appropriate

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
ntpd: let user know if spike was detected

function                                             old     new   delta
update_local_clock                                   861     943     +82

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
ntpd: promote log level 3 to production

Without it, peer selection logic is hard to debug

function                                             old     new   delta
update_local_clock                                   861     982    +121
select_and_cluster                                   962    1065    +103
common_ping_main                                    1788    1821     +33
huft_build                                          1287    1296      +9
chpst_main                                           708     704      -4
INET6_resolve                                        127     119      -8
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 4/2 up/down: 266/-12)           Total: 254 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
ntpd: comment out "spike detection" code

function                                             old     new   delta
update_local_clock                                   982     835    -147

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
ntpd: do not invalidate datapoints after step

Used to set p->filter_datapoint[i].d_dispersion = MAXDISP
and clear reachable bits, but this proved to be too agressive:
after step (tested with suspinding laptop for ~30 secs),
this caused all previous data to be considered invalid,
making us needing to collect full ~8 datapoins per peer
after step in order to start trusting them.
In turn, this was making poll interval decrease even after
step was done. (Poll interval decreases already before step
in this scenario, because we see large offsets and end up with
no good peer to select).

function                                             old     new   delta
reset_peer_stats                                     157     139     -18

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
ntpd: speed up resyncing if our clock is seriously off

function                                             old     new   delta
recv_and_process_peer_pkt                            892     922     +30

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>