Zombie keep their previous upgrade_time when they revive

[Fris0uman]

Summary

SUMMARY: Bugfixes "Reviving does not speed up evolution"

Purpose of change

Fixes #12439
Reviving does not speed up zombie evolution

Describe the solution

Pass upgrade_time to make_corpse()
In make_corpse()if the monster has the REVIVE flag store upgrade_time as a var
In init_from_item get upggrade_time from the corpse item

Describe alternatives you've considered

Testing

Debug Kill zombies
Use debug function of VS to check that the var is properly set
Wait fro them to revive
Use debug to check that upgrade_time is properly set back to what it was on death

Additional context