init/service_parser: Add arguments `window' and `target' for `critical'

The critical services can now using the interface `critical
[window=<fatal crash window mins>] [target=<fatal reboot target>]` to
setup the timing window that when there are more than 4 crashes in it,
the init will regard it as a fatal system error and reboot the system.

Config `window=${zygote.critical_window.minute:-off}' and
`target=zygote-fatal' for all system-server services, so platform that
configures ro.boot.zygote_critical_window can escape the system-server
crash-loop via init fatal handler.

Bug: 146818493
Change-Id: Ib2dc253616be6935ab9ab52184a1b6394665e813