ch: Introduce flags to virCHProcessStop()

ch: Introduce flags to virCHProcessStop()

A caller (e.g. chDomainDestroyFlags()) might want to chose
whether to kill emulator process forcefully or gracefully (the
@force argument of virProcessKillPainfully()). Invent a flag to
virCHProcessStop() for this. And to keep consistent behaviour,
pass the flag everywhere for now.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>