procd: add timing to start/stop logging

procd: add timing to start/stop logging

Shows how long an initd task took, for example:

 procd: stop /etc/init.d/dropbear running - took 0.088824s
 procd: Update service dnsmasq
 procd: Update instance dnsmasq::dnsmasq
 procd: running /etc/init.d/dnsmasq running
 procd: start /etc/init.d/dnsmasq running
 procd: stop /etc/init.d/dnsmasq running - took 0.092586s

 v2: rename variables, correct time unit
 v3: use CLOCK_MONOTONIC_RAW to prevent issues with NTP and adjtime

Signed-off-by: Karl Vogel <karl.vogel@gmail.com>